app_sms.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2004 - 2005, Adrian Kennard, rights assigned to Digium
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
/*! \file
 *
 * \brief SMS application - ETSI ES 201 912 protocol 1 implementation
 *
 * \par Development notes
 * \note The ETSI standards are available free of charge from ETSI at
 *  http://pda.etsi.org/pda/queryform.asp
 *  Among the relevant documents here we have:
 *
 *  ES 201 912  SMS for PSTN/ISDN
 *  TS 123 040  Technical realization of SMS
 *
 *
 * \ingroup applications
 *
 * \author Adrian Kennard (for the original protocol 1 code)
 * \author Filippo Grassilli (Hyppo) - protocol 2 support
 *         Not fully tested, under development
 * \author Itzan Huerta - Testing and debugging for Telefónica DOMO Mensajes (Spain) phones using protocol 2.
 */
 
/*** MODULEINFO
    <support_level>extended</support_level>
 ***/
 
#include "asterisk.h"
 
#include <dirent.h>
#include <ctype.h>
#include <sys/stat.h>
 
#include "asterisk/paths.h"  /* use ast_config_AST_SPOOL_DIR and LOG_DIR */
#include "asterisk/lock.h"
#include "asterisk/file.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/alaw.h"
#include "asterisk/callerid.h"
#include "asterisk/utils.h"
#include "asterisk/app.h"
#include "asterisk/format_cache.h"
 
/*** DOCUMENTATION
    <application name="SMS" language="en_US">
        <since>
            <version>1.6.1.0</version>
        </since>
        <synopsis>
            Communicates with SMS service centres and SMS capable analogue phones.
        </synopsis>
        <syntax>
            <parameter name="name" required="true">
                <para>The name of the queue used in <filename>/var/spool/asterisk/sms</filename></para>
            </parameter>
            <parameter name="options">
                <optionlist>
                    <option name="a">
                        <para>Answer, i.e. send initial FSK packet.</para>
                    </option>
                    <option name="s">
                        <para>Act as service centre talking to a phone.</para>
                    </option>
                    <option name="t">
                        <para>Use protocol 2 (default used is protocol 1).</para>
                    </option>
                    <option name="p">
                        <para>Set the initial delay to N ms (default is <literal>300</literal>).
                        addr and body are a deprecated format to send messages out.</para>
                    </option>
                    <option name="r">
                        <para>Set the Status Report Request (SRR) bit.</para>
                    </option>
                    <option name="o">
                        <para>The body should be coded as octets not 7-bit symbols.</para>
                    </option>
                    <option name="n">
                        <para>Do not log any SMS content to log file (privacy).</para>
                    </option>
                </optionlist>
            </parameter>
            <parameter name="addr" />
            <parameter name="body" />
        </syntax>
        <description>
            <para>SMS handles exchange of SMS data with a call to/from SMS capable phone or SMS PSTN service center.
            Can send and/or receive SMS messages. Works to ETSI ES 201 912; compatible with BT SMS PSTN service in
            UK and Telecom Italia in Italy. It has also been tested to work with DOMO phones from Telefónica Spain.</para>
            <para>Typical usage is to use to handle calls from the SMS service centre CLI, or to set up a call using
            <literal>outgoing</literal> or manager interface to connect service centre to SMS().</para>
            <para>"Messages are processed as per text file message queues. smsq (a separate software) is a command to
            generate message queues and send messages.</para>
            <note><para>The protocol has tight delay bounds. Please use short frames and disable/keep short the
            jitter buffer on the ATA to make sure that responses (ACK etc.) are received in time.</para>
            <para>It is also important to adjust the gain dB of the ATA. Some Telefónica DOMO Mensajes phones may require
            the gain to be set to +3dB, and others even up to +6dB, in order to work.</para></note>
        </description>
    </application>
 ***/
 
/* #define OUTALAW */        /* enable this to output Alaw rather than linear */
 
/* ToDo */
/* Add full VP support */
/* Handle status report messages (generation and reception) */
/* Time zones on time stamps */
/* user ref field */
 
static volatile unsigned char message_ref;  /* arbitary message ref */
static volatile unsigned int seq;           /* arbitrary message sequence number for unqiue files */
 
static char log_file[255];
 
static char *app = "SMS";
 
/*
 * 80 samples of a single period of the wave. At 8000 Hz, it means these
 * are the samples of a 100 Hz signal.
 * To pick the two carriers (1300Hz for '1' and 2100 Hz for '0') used by
 * the modulation, we should take one every 13 and 21 samples respectively.
 */
static const signed short wave[] = {
    0, 392, 782, 1167, 1545, 1913, 2270, 2612, 2939, 3247, 3536, 3802, 4045, 4263, 4455, 4619, 4755, 4862, 4938, 4985,
    5000, 4985, 4938, 4862, 4755, 4619, 4455, 4263, 4045, 3802, 3536, 3247, 2939, 2612, 2270, 1913, 1545, 1167, 782, 392,
    0, -392, -782, -1167,
     -1545, -1913, -2270, -2612, -2939, -3247, -3536, -3802, -4045, -4263, -4455, -4619, -4755, -4862, -4938, -4985, -5000,
    -4985, -4938, -4862,
    -4755, -4619, -4455, -4263, -4045, -3802, -3536, -3247, -2939, -2612, -2270, -1913, -1545, -1167, -782, -392
};
 
#ifdef OUTALAW
static unsigned char wavea[80];
typedef unsigned char output_t;
static const output_t *wave_out = wavea;    /* outgoing samples */
#define __OUT_FMT ast_format_alaw
#else
typedef signed short output_t;
static const output_t *wave_out = wave;     /* outgoing samples */
#define __OUT_FMT ast_format_slin
#endif
 
#define OSYNC_BITS  80                      /* initial sync bits */
 
/*!
 * The SMS spec ETSI ES 201 912 defines two protocols with different message types.
 * Also note that the high bit is used to indicate whether the message
 * is complete or not, but in two opposite ways:
 * for Protocol 1, 0x80 means that the message is complete;
 * for Protocol 2, 0x00 means that the message is complete;
 */
enum message_types {
    DLL_SMS_MASK        = 0x7f,             /* mask for the valid bits */
 
    /* Protocol 1 values */
    DLL1_SMS_DATA       = 0x11,             /* data packet */
    DLL1_SMS_ERROR      = 0x12,
    DLL1_SMS_EST        = 0x13,             /* start the connection */
    DLL1_SMS_REL        = 0x14,             /* end the connection */
    DLL1_SMS_ACK        = 0x15,
    DLL1_SMS_NACK       = 0x16,
 
    DLL1_SMS_COMPLETE   = 0x80,             /* packet is complete */
    DLL1_SMS_MORE       = 0x00,             /* more data to follow */
 
    /* Protocol 2 values */
    DLL2_SMS_EST        = 0x7f,             /* magic number. No message body */
    DLL2_SMS_INFO_MO    = 0x10,
    DLL2_SMS_INFO_MT    = 0x11,
    DLL2_SMS_INFO_STA   = 0x12,
    DLL2_SMS_NACK       = 0x13,
    DLL2_SMS_ACK0       = 0x14,             /* ack even-numbered frame */
    DLL2_SMS_ACK1       = 0x15,             /* ack odd-numbered frame */
    DLL2_SMS_ENQ        = 0x16,
    DLL2_SMS_REL        = 0x17,             /* end the connection */
 
    DLL2_SMS_COMPLETE   = 0x00,             /* packet is complete */
    DLL2_SMS_MORE       = 0x80,             /* more data to follow */
};
 
/* SMS 7 bit character mapping to UCS-2 */
static const unsigned short defaultalphabet[] = {
    0x0040, 0x00A3, 0x0024, 0x00A5, 0x00E8, 0x00E9, 0x00F9, 0x00EC,
    0x00F2, 0x00E7, 0x000A, 0x00D8, 0x00F8, 0x000D, 0x00C5, 0x00E5,
    0x0394, 0x005F, 0x03A6, 0x0393, 0x039B, 0x03A9, 0x03A0, 0x03A8,
    0x03A3, 0x0398, 0x039E, 0x00A0, 0x00C6, 0x00E6, 0x00DF, 0x00C9,
    ' ', '!', '"', '#', 164, '%', '&', 39, '(', ')', '*', '+', ',', '-', '.', '/',
    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ':', ';', '<', '=', '>', '?',
    161, 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
    'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 196, 214, 209, 220, 167,
    191, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
    'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 228, 246, 241, 252, 224,
};
 
static const unsigned short escapes[] = {
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x000C, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0x005E, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0x007B, 0x007D, 0, 0, 0, 0, 0, 0x005C,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x005B, 0x007E, 0x005D, 0,
    0x007C, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0x20AC, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
};
 
#define SMSLEN      160          /*!< max SMS length */
#define SMSLEN_8    140          /*!< max SMS length for 8-bit char */
 
typedef struct sms_s {
    unsigned char hangup;        /*!< we are done... */
    unsigned char err;           /*!< set for any errors */
    unsigned char sent_rel:1;     /*!< have sent REL message... */
    unsigned char smsc:1;        /*!< we are SMSC */
    unsigned char rx:1;          /*!< this is a received message */
    unsigned char nolog:1;       /*!< do not log plain text SMS content (privacy) */
    char queue[30];              /*!< queue name */
    char oa[20];                 /*!< originating address */
    char da[20];                 /*!< destination address */
    struct timeval scts;         /*!< time stamp, UTC */
    unsigned char pid;           /*!< protocol ID */
    unsigned char dcs;           /*!< data coding scheme */
    short mr;                    /*!< message reference - actually a byte, but use -1 for not set */
    int udl;                     /*!< user data length */
    int udhl;                    /*!< user data header length */
    unsigned char srr:1;         /*!< Status Report request */
    unsigned char udhi:1;        /*!< User Data Header required, even if length 0 */
    unsigned char rp:1;          /*!< Reply Path */
    unsigned int vp;             /*!< validity period in minutes, 0 for not set */
    unsigned short ud[SMSLEN];   /*!< user data (message), UCS-2 coded */
    unsigned char udh[SMSLEN];   /*!< user data header */
    char cli[20];                /*!< caller ID */
    unsigned char ophase;        /*!< phase (0-79) for 0 and 1 frequencies (1300Hz and 2100Hz) */
    unsigned char ophasep;       /*!< phase (0-79) for 1200 bps */
    unsigned char obyte;         /*!< byte being sent */
    unsigned int opause;         /*!< silent pause before sending (in sample periods) */
    unsigned char obitp;         /*!< bit in byte */
    unsigned char osync;         /*!< sync bits to send */
    unsigned char obytep;        /*!< byte in data */
    unsigned char obyten;        /*!< bytes in data */
    unsigned char omsg[256];     /*!< data buffer (out) */
    unsigned char imsg[250];     /*!< data buffer (in) */
    signed long long ims0,
        imc0,
        ims1,
        imc1;                    /*!< magnitude averages sin/cos 0/1 */
    unsigned int idle;
    unsigned short imag;         /*!< signal level */
    unsigned char ips0;          /*!< phase sin for bit 0, start at  0 inc by 21 mod 80 */
    unsigned char ips1;          /*!< phase cos for bit 0, start at 20 inc by 21 mod 80 */
    unsigned char ipc0;          /*!< phase sin for bit 1, start at  0 inc by 13 mod 80 */
    unsigned char ipc1;          /*!< phase cos for bit 1, start at 20 inc by 13 mod 80 */
    unsigned char ibitl;         /*!< last bit */
    unsigned char ibitc;         /*!< bit run length count */
    unsigned char iphasep;       /*!< bit phase (0-79) for 1200 bps */
    unsigned char ibitn;         /*!< bit number in byte being received */
    unsigned char ibytev;        /*!< byte value being received */
    unsigned char ibytep;        /*!< byte pointer in message */
    unsigned char ibytec;        /*!< byte checksum for message */
    unsigned char ierr;          /*!< error flag */
    unsigned char ibith;         /*!< history of last bits */
    unsigned char ibitt;         /*!< total of 1's in last 3 bytes */
    /* more to go here */
 
    int opause_0;                /*!< initial delay in ms, p() option */
    int protocol;                /*!< ETSI SMS protocol to use (passed at app call) */
    int oseizure;                /*!< protocol 2: channel seizure bits to send */
    int framenumber;             /*!< protocol 2: frame number (for sending ACK0 or ACK1) */
    char udtxt[SMSLEN];          /*!< user data (message), PLAIN text */
} sms_t;
 
/* different types of encoding */
#define is7bit(dcs)  ( ((dcs) & 0xC0) ? (!((dcs) & 4) ) : (((dcs) & 0xc) == 0) )
#define is8bit(dcs)  ( ((dcs) & 0xC0) ? ( ((dcs) & 4) ) : (((dcs) & 0xc) == 4) )
#define is16bit(dcs) ( ((dcs) & 0xC0) ? 0               : (((dcs) & 0xc) == 8) )
 
static void sms_messagetx(sms_t *h);
 
/*! \brief copy number, skipping non digits apart from leading + */
static void numcpy(char *d, char *s)
{
    if (*s == '+') {
        *d++ = *s++;
    }
    while (*s) {
        if (isdigit(*s)) {
            *d++ = *s;
        }
        s++;
    }
    *d = 0;
}
 
/*! \brief static, return a date/time in ISO format */
static char *isodate(time_t t, char *buf, int len)
{
    struct ast_tm tm;
    struct timeval local = { t, 0 };
    ast_localtime(&local, &tm, NULL);
    ast_strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm);
    return buf;
}
 
/*! \brief Reads next UCS character from NUL terminated UTF-8 string and advance pointer */
/* for non valid UTF-8 sequences, returns character as is */
/* Does not advance pointer for null termination */
static long utf8decode(unsigned char **pp)
{
    unsigned char *p = *pp;
    if (!*p) {
        return 0;                           /* null termination of string */
    }
    (*pp)++;
    if (*p < 0xC0) {
        return *p;                          /* ascii or continuation character */
    }
    if (*p < 0xE0) {
        if (*p < 0xC2 || (p[1] & 0xC0) != 0x80) {
            return *p;                      /* not valid UTF-8 */
        }
        (*pp)++;
        return ((*p & 0x1F) << 6) + (p[1] & 0x3F);
    }
    if (*p < 0xF0) {
        if ((*p == 0xE0 && p[1] < 0xA0) || (p[1] & 0xC0) != 0x80 || (p[2] & 0xC0) != 0x80) {
            return *p;                      /* not valid UTF-8 */
        }
        (*pp) += 2;
        return ((*p & 0x0F) << 12) + ((p[1] & 0x3F) << 6) + (p[2] & 0x3F);
    }
    if (*p < 0xF8) {
        if ((*p == 0xF0 && p[1] < 0x90) || (p[1] & 0xC0) != 0x80 || (p[2] & 0xC0) != 0x80 || (p[3] & 0xC0) != 0x80) {
            return *p;                      /* not valid UTF-8 */
        }
        (*pp) += 3;
        return ((*p & 0x07) << 18) + ((p[1] & 0x3F) << 12) + ((p[2] & 0x3F) << 6) + (p[3] & 0x3F);
    }
    if (*p < 0xFC) {
        if ((*p == 0xF8 && p[1] < 0x88) || (p[1] & 0xC0) != 0x80 || (p[2] & 0xC0) != 0x80 || (p[3] & 0xC0) != 0x80
            || (p[4] & 0xC0) != 0x80) {
            return *p;                      /* not valid UTF-8 */
        }
        (*pp) += 4;
        return ((*p & 0x03) << 24) + ((p[1] & 0x3F) << 18) + ((p[2] & 0x3F) << 12) + ((p[3] & 0x3F) << 6) + (p[4] & 0x3F);
    }
    if (*p < 0xFE) {
        if ((*p == 0xFC && p[1] < 0x84) || (p[1] & 0xC0) != 0x80 || (p[2] & 0xC0) != 0x80 || (p[3] & 0xC0) != 0x80
            || (p[4] & 0xC0) != 0x80 || (p[5] & 0xC0) != 0x80) {
            return *p;                      /* not valid UTF-8 */
        }
        (*pp) += 5;
        return ((*p & 0x01) << 30) + ((p[1] & 0x3F) << 24) + ((p[2] & 0x3F) << 18) + ((p[3] & 0x3F) << 12) + ((p[4] & 0x3F) << 6) + (p[5] & 0x3F);
    }
    return *p;                              /* not sensible */
}
 
/*! \brief takes a binary header (udhl bytes at udh) and UCS-2 message (udl characters at ud) and packs in to o using SMS 7 bit character codes */
/* The return value is the number of septets packed in to o, which is internally limited to SMSLEN */
/* o can be null, in which case this is used to validate or count only */
/* if the input contains invalid characters then the return value is -1 */
static int packsms7(unsigned char *o, int udhl, unsigned char *udh, int udl, unsigned short *ud)
{
    unsigned char p = 0;                    /* output pointer (bytes) */
    unsigned char b = 0;                    /* bit position */
    unsigned char n = 0;                    /* output character count */
    unsigned char dummy[SMSLEN];
 
    if (o == NULL) {                        /* output to a dummy buffer if o not set */
        o = dummy;
    }
 
    if (udhl) {                             /* header */
        o[p++] = udhl;
        b = 1;
        n = 1;
        while (udhl--) {
            o[p++] = *udh++;
            b += 8;
            while (b >= 7) {
                b -= 7;
                n++;
            }
            if (n >= SMSLEN)
                return n;
        }
        if (b) {
            b = 7 - b;
            if (++n >= SMSLEN)
                return n;
        }                                   /* filling to septet boundary */
    }
    o[p] = 0;
    /* message */
    while (udl--) {
        long u;
        unsigned char v;
        u = *ud++;
        /* XXX 0 is invalid ? */
        /* look up in defaultalphabet[]. If found, v is the 7-bit code */
        for (v = 0; v < 128 && defaultalphabet[v] != u; v++);
        if (v == 128 /* not found */ && u && n + 1 < SMSLEN) {
            /* if not found, look in the escapes table (we need 2 bytes) */
            for (v = 0; v < 128 && escapes[v] != u; v++);
            if (v < 128) {  /* escaped sequence, esc + v */
                /* store the low (8-b) bits in o[p], the remaining bits in o[p+1] */
                o[p] |= (27 << b);          /* the low bits go into o[p] */
                b += 7;
                if (b >= 8) {
                    b -= 8;
                    p++;
                    o[p] = (27 >> (7 - b));
                }
                n++;
            }
        }
        if (v == 128)
            return -1;                      /* invalid character */
        /* store, same as above */
        o[p] |= (v << b);
        b += 7;
        if (b >= 8) {
            b -= 8;
            p++;
            o[p] = (v >> (7 - b));
        }
        if (++n >= SMSLEN)
            return n;
    }
    return n;
}
 
/*! \brief takes a binary header (udhl bytes at udh) and UCS-2 message (udl characters at ud)
 * and packs in to o using 8 bit character codes.
 * The return value is the number of bytes packed in to o, which is internally limited to 140.
 * o can be null, in which case this is used to validate or count only.
 * if the input contains invalid characters then the return value is -1
 */
static int packsms8(unsigned char *o, int udhl, unsigned char *udh, int udl, unsigned short *ud)
{
    unsigned char p = 0;
    unsigned char dummy[SMSLEN_8];
 
    if (o == NULL)
        o = dummy;
    /* header - no encoding */
    if (udhl) {
        o[p++] = udhl;
        while (udhl--) {
            o[p++] = *udh++;
            if (p >= SMSLEN_8) {
                return p;
            }
        }
    }
    while (udl--) {
        long u;
        u = *ud++;
        if (u < 0 || u > 0xFF) {
            return -1;                      /* not valid */
        }
        o[p++] = u;
        if (p >= SMSLEN_8) {
            return p;
        }
    }
    return p;
}
 
/*! \brief takes a binary header (udhl bytes at udh) and UCS-2
    message (udl characters at ud) and packs in to o using 16 bit
    UCS-2 character codes
    The return value is the number of bytes packed in to o, which is
    internally limited to 140
    o can be null, in which case this is used to validate or count
    only if the input contains invalid characters then
    the return value is -1 */
static int packsms16(unsigned char *o, int udhl, unsigned char *udh, int udl, unsigned short *ud)
{
    unsigned char p = 0;
    unsigned char dummy[SMSLEN_8];
 
    if (o == NULL) {
        o = dummy;
    }
    /* header - no encoding */
    if (udhl) {
        o[p++] = udhl;
        while (udhl--) {
            o[p++] = *udh++;
            if (p >= SMSLEN_8) {
                return p;
            }
        }
    }
    while (udl--) {
        long u;
        u = *ud++;
        o[p++] = (u >> 8);
        if (p >= SMSLEN_8) {
            return p - 1;                   /* could not fit last character */
        }
        o[p++] = u;
        if (p >= SMSLEN_8) {
            return p;
        }
    }
    return p;
}
 
/*! \brief general pack, with length and data,
    returns number of bytes of target used */
static int packsms(unsigned char dcs, unsigned char *base, unsigned int udhl, unsigned char *udh, int udl, unsigned short *ud)
{
    unsigned char *p = base;
    if (udl == 0) {
        *p++ = 0;                           /* no user data */
    } else {
 
        int l = 0;
        if (is7bit(dcs)) {                  /* 7 bit */
            if ((l = packsms7(p + 1, udhl, udh, udl, ud)) < 0) {
                l = 0;
            }
            *p++ = l;
            p += (l * 7 + 7) / 8;
        } else if (is8bit(dcs)) {           /* 8 bit */
            if ((l = packsms8(p + 1, udhl, udh, udl, ud)) < 0) {
                l = 0;
            }
            *p++ = l;
            p += l;
        } else {                            /* UCS-2 */
            if ((l = packsms16(p + 1, udhl, udh, udl, ud)) < 0) {
                l = 0;
            }
            *p++ = l;
            p += l;
        }
    }
    return p - base;
}
 
 
/*! \brief pack a date and return */
static void packdate(unsigned char *o, time_t w)
{
    struct ast_tm t;
    struct timeval topack = { w, 0 };
    int z;
 
    ast_localtime(&topack, &t, NULL);
#if defined(__FreeBSD__) || defined(__OpenBSD__) || defined( __NetBSD__ ) || defined(__APPLE__) || defined(__CYGWIN__)
    z = -t.tm_gmtoff / 60 / 15;
#else
    z = timezone / 60 / 15;
#endif
    *o++ = ((t.tm_year % 10) << 4) + (t.tm_year % 100) / 10;
    *o++ = (((t.tm_mon + 1) % 10) << 4) + (t.tm_mon + 1) / 10;
    *o++ = ((t.tm_mday % 10) << 4) + t.tm_mday / 10;
    *o++ = ((t.tm_hour % 10) << 4) + t.tm_hour / 10;
    *o++ = ((t.tm_min % 10) << 4) + t.tm_min / 10;
    *o++ = ((t.tm_sec % 10) << 4) + t.tm_sec / 10;
    if (z < 0) {
        *o++ = (((-z) % 10) << 4) + (-z) / 10 + 0x08;
    } else {
        *o++ = ((z % 10) << 4) + z / 10;
    }
}
 
/*! \brief unpack a date and return */
static struct timeval unpackdate(unsigned char *i)
{
    struct ast_tm t;
 
    t.tm_year = 100 + (i[0] & 0xF) * 10 + (i[0] >> 4);
    t.tm_mon = (i[1] & 0xF) * 10 + (i[1] >> 4) - 1;
    t.tm_mday = (i[2] & 0xF) * 10 + (i[2] >> 4);
    t.tm_hour = (i[3] & 0xF) * 10 + (i[3] >> 4);
    t.tm_min = (i[4] & 0xF) * 10 + (i[4] >> 4);
    t.tm_sec = (i[5] & 0xF) * 10 + (i[5] >> 4);
    t.tm_isdst = 0;
    if (i[6] & 0x08) {
        t.tm_min += 15 * ((i[6] & 0x7) * 10 + (i[6] >> 4));
    } else {
        t.tm_min -= 15 * ((i[6] & 0x7) * 10 + (i[6] >> 4));
    }
 
    return ast_mktime(&t, NULL);
}
 
/*! \brief unpacks bytes (7 bit encoding) at i, len l septets,
    and places in udh and ud setting udhl and udl. udh not used
    if udhi not set */
static void unpacksms7(unsigned char *i, unsigned char l, unsigned char *udh, size_t udh_size,
    int *udhl, unsigned short *ud, size_t ud_size, int *udl, char udhi)
{
    unsigned char b = 0, p = 0;
    unsigned short *o = ud;
    unsigned short *o_end = ud + ud_size;
    unsigned char *h = udh;
    unsigned char *h_end = udh + udh_size;
    size_t stored_udhl = 0;
    *udhl = 0;
    if (udhi && l) {                        /* header */
        int hlen = i[p];
        if (hlen) {
            b = 1;
            p++;
            l--;
            while (hlen-- && l) {
                if (h < h_end) {
                    *h++ = i[p];
                    stored_udhl++;
                }
                p++;
                b += 8;
                while (b >= 7) {
                    b -= 7;
                    l--;
                    if (!l) {
                        break;
                    }
                }
            }
            /* adjust for fill, septets */
            if (b) {
                b = 7 - b;
                l--;
            }
        }
    }
    while (l--) {
        unsigned char v;
        if (b < 2) {
            v = ((i[p] >> b) & 0x7F);       /* everything in one byte */
        } else {
            v = ((((i[p] >> b) + (i[p + 1] << (8 - b)))) & 0x7F);
        }
        b += 7;
        if (b >= 8) {
            b -= 8;
            p++;
        }
        /* 0x00A0 is the encoding of ESC (27) in defaultalphabet */
        if (o > ud && o[-1] == 0x00A0 && escapes[v]) {
            o[-1] = escapes[v];
        } else if (o < o_end) {
            *o++ = defaultalphabet[v];
        }
    }
    *udl = o - ud;
    *udhl = stored_udhl;
}
 
/*! \brief unpacks bytes (8 bit encoding) at i, len l septets,
 *  and places in udh and ud setting udhl and udl. udh not used
 *  if udhi not set.
 */
static void unpacksms8(unsigned char *i, unsigned char l, unsigned char *udh, size_t udh_size,
    int *udhl, unsigned short *ud, size_t ud_size, int *udl, char udhi)
{
    unsigned short *o = ud;
    unsigned short *o_end = ud + ud_size;
    unsigned char *h = udh;
    unsigned char *h_end = udh + udh_size;
    size_t stored_udhl = 0;
    *udhl = 0;
    if (udhi) {
        int n = *i;
        if (n) {
            i++;
            l--;
            while (l && n) {
                l--;
                n--;
                if (h < h_end) {
                    *h++ = *i;
                    stored_udhl++;
                }
                i++;
            }
        }
    }
    while (l--) {
        if (o < o_end) {
            *o++ = *i;               /* not to UTF-8 as explicitly 8 bit coding in DCS */
        }
        i++;
    }
    *udl = o - ud;
    *udhl = stored_udhl;
}
 
/*! \brief unpacks bytes (16 bit encoding) at i, len l septets,
    and places in udh and ud setting udhl and udl.
    udh not used if udhi not set */
static void unpacksms16(unsigned char *i, unsigned char l, unsigned char *udh, size_t udh_size,
    int *udhl, unsigned short *ud, size_t ud_size, int *udl, char udhi)
{
    unsigned short *o = ud;
    unsigned short *o_end = ud + ud_size;
    unsigned char *h = udh;
    unsigned char *h_end = udh + udh_size;
    size_t stored_udhl = 0;
    *udhl = 0;
    if (udhi) {
        int n = *i;
        if (n) {
            i++;
            l--;
            while (l && n) {
                l--;
                n--;
                if (h < h_end) {
                    *h++ = *i;
                    stored_udhl++;
                }
                i++;
            }
        }
    }
    while (l--) {
        int v = *i++;
        if (l && l--) {
            v = (v << 8) + *i++;
        }
        if (o < o_end) {
            *o++ = v;
        }
    }
    *udl = o - ud;
    *udhl = stored_udhl;
}
 
/*! \brief general unpack - starts with length byte (octet or septet) and returns number of bytes used, inc length */
static int unpacksms(unsigned char dcs, unsigned char *i, unsigned char *udh, size_t udh_size,
    int *udhl, unsigned short *ud, size_t ud_size, int *udl, char udhi)
{
    int l = *i++;
    if (is7bit(dcs)) {
        unpacksms7(i, l, udh, udh_size, udhl, ud, ud_size, udl, udhi);
        l = (l * 7 + 7) / 8;                /* adjust length to return */
    } else if (is8bit(dcs)) {
        unpacksms8(i, l, udh, udh_size, udhl, ud, ud_size, udl, udhi);
    } else {
        l += l % 2;
        unpacksms16(i, l, udh, udh_size, udhl, ud, ud_size, udl, udhi);
    }
    return l + 1;
}
 
/*! \brief unpack an address from i, return byte length, unpack to o */
static unsigned char unpackaddress(char *o, size_t o_size, unsigned char *i)
{
    unsigned char l = i[0], p;
    char *o_end;
 
    if (!o_size) {
        return (l + 5) / 2;
    }
 
    o_end = o + o_size - 1;
    if (i[1] == 0x91) {
        if (o < o_end) {
            *o++ = '+';
        }
    }
    for (p = 0; p < l; p++) {
        if (o < o_end) {
            if (p & 1) {
                *o++ = (i[2 + p / 2] >> 4) + '0';
            } else {
                *o++ = (i[2 + p / 2] & 0xF) + '0';
            }
        }
    }
    *o = 0;
    return (l + 5) / 2;
}
 
/*! \brief store an address at o, and return number of bytes used */
static unsigned char packaddress(unsigned char *o, char *i)
{
    unsigned char p = 2;
    o[0] = 0;                               /* number of bytes */
    if (*i == '+') {                        /* record as bit 0 in byte 1 */
        i++;
        o[1] = 0x91;
    } else {
        o[1] = 0x81;
    }
    for ( ; *i ; i++) {
        if (!isdigit(*i)) {                 /* ignore non-digits */
            continue;
        }
        if (o[0] & 1) {
            o[p++] |= ((*i & 0xF) << 4);
        } else {
            o[p] = (*i & 0xF);
        }
        o[0]++;
    }
    if (o[0] & 1) {
        o[p++] |= 0xF0;                     /* pad */
    }
    return p;
}
 
/*! \brief Log the output, and remove file */
static void sms_log(sms_t * h, char status)
{
    int o;
 
    if (*h->oa == '\0' && *h->da == '\0') {
        return;
    }
    o = open(log_file, O_CREAT | O_APPEND | O_WRONLY, AST_FILE_MODE);
    if (o >= 0) {
        char line[1000], mrs[3] = "", *p;
        char buf[30];
        unsigned char n;
 
        if (h->mr >= 0) {
            snprintf(mrs, sizeof(mrs), "%02hhX", (unsigned char)h->mr);
        }
        snprintf(line, sizeof(line), "%s %c%c%c%s %s %s %s ",
            isodate(time(NULL), buf, sizeof(buf)),
            status, h->rx ? 'I' : 'O', h->smsc ? 'S' : 'M', mrs, h->queue,
            S_OR(h->oa, "-"), S_OR(h->da, "-") );
        p = line + strlen(line);
 
        if (h->nolog) {
            p += snprintf(p, 1000 - strlen(line), "udl=%d", h->udl);
        } else {
            for (n = 0; n < h->udl; n++) {
                if (h->ud[n] == '\\') {
                    *p++ = '\\';
                    *p++ = '\\';
                } else if (h->ud[n] == '\n') {
                    *p++ = '\\';
                    *p++ = 'n';
                } else if (h->ud[n] == '\r') {
                    *p++ = '\\';
                    *p++ = 'r';
                } else if (h->ud[n] < 32 || h->ud[n] == 127) {
                    *p++ = 0xbf;
                } else {
                    *p++ = h->ud[n];
                }
            }
        }
        *p++ = '\n';
        *p = 0;
        if (write(o, line, strlen(line)) < 0) {
            ast_log(LOG_WARNING, "write() failed: %s\n", strerror(errno));
        }
        close(o);
    }
    *h->oa = *h->da = h->udl = 0;
}
 
/*! \brief parse and delete a file */
static void sms_readfile(sms_t * h, char *fn)
{
    char line[1000];
    FILE *s;
    char dcsset = 0;                        /* if DSC set */
    ast_log(LOG_NOTICE, "Sending %s\n", fn);
    h->rx = h->udl = *h->oa = *h->da = h->pid = h->srr = h->udhi = h->rp = h->vp = h->udhl = 0;
    h->mr = -1;
    h->dcs = 0xF1;                          /* normal messages class 1 */
    h->scts = ast_tvnow();
    s = fopen(fn, "r");
    if (s) {
        if (unlink(fn)) {                   /* concurrent access, we lost */
            fclose(s);
            return;
        }
        while (fgets (line, sizeof(line), s)) { /* process line in file */
            char *p;
            void *pp = &p;
            for (p = line; *p && *p != '\n' && *p != '\r'; p++);
            *p = 0;                         /* strip eoln */
            p = line;
            if (!*p || *p == ';') {
                continue;                   /* blank line or comment, ignore */
            }
            while (isalnum(*p)) {
                *p = tolower (*p);
                p++;
            }
            while (isspace (*p)) {
                *p++ = 0;
            }
            if (*p == '=') {
                *p++ = 0;
                if (!strcmp(line, "ud")) {  /* parse message (UTF-8) */
                    unsigned char o = 0;
                    memcpy(h->udtxt, p, SMSLEN); /* for protocol 2 */
                    while (*p && o < SMSLEN) {
                        h->ud[o++] = utf8decode(pp);
                        p++;
                    }
                    h->udl = o;
                    if (*p) {
                        ast_log(LOG_WARNING, "UD too long in %s\n", fn);
                    }
                } else {
                    while (isspace (*p)) {
                        p++;
                    }
                    if (!strcmp(line, "oa") && strlen(p) < sizeof(h->oa)) {
                        numcpy (h->oa, p);
                    } else if (!strcmp(line, "da") && strlen(p) < sizeof(h->oa)) {
                        numcpy (h->da, p);
                    } else if (!strcmp(line, "pid")) {
                        h->pid = atoi(p);
                    } else if (!strcmp(line, "dcs")) {
                        h->dcs = atoi(p);
                        dcsset = 1;
                    } else if (!strcmp(line, "mr")) {
                        h->mr = atoi(p);
                    } else if (!strcmp(line, "srr")) {
                        h->srr = (atoi(p) ? 1 : 0);
                    } else if (!strcmp(line, "vp")) {
                        h->vp = atoi(p);
                    } else if (!strcmp(line, "rp")) {
                        h->rp = (atoi(p) ? 1 : 0);
                    } else if (!strcmp(line, "scts")) {    /* get date/time */
                        int Y, m, d, H, M, S;
                        /* XXX Why aren't we using ast_strptime here? */
                        if (sscanf(p, "%4d-%2d-%2dT%2d:%2d:%2d", &Y, &m, &d, &H, &M, &S) == 6) {
                            struct ast_tm t = { 0, };
                            t.tm_year = Y - 1900;
                            t.tm_mon = m - 1;
                            t.tm_mday = d;
                            t.tm_hour = H;
                            t.tm_min = M;
                            t.tm_sec = S;
                            t.tm_isdst = -1;
                            h->scts = ast_mktime(&t, NULL);
                            if (h->scts.tv_sec == 0) {
                                ast_log(LOG_WARNING, "Bad date/timein %s: %s", fn, p);
                            }
                        }
                    } else {
                        ast_log(LOG_WARNING, "Cannot parse in %s: %s=%si\n", fn, line, p);
                    }
                }
            } else if (*p == '#') {                   /* raw hex format */
                *p++ = 0;
                if (*p == '#') {
                    p++;
                    if (!strcmp(line, "ud")) {        /* user data */
                        int o = 0;
                        while (*p && o < SMSLEN) {
                            if (isxdigit(*p) && isxdigit(p[1]) && isxdigit(p[2]) && isxdigit(p[3])) {
                                h->ud[o++] =
                                    (((isalpha(*p) ? 9 : 0) + (*p & 0xF)) << 12) +
                                    (((isalpha(p[1]) ? 9 : 0) + (p[1] & 0xF)) << 8) +
                                    (((isalpha(p[2]) ? 9 : 0) + (p[2] & 0xF)) << 4) + ((isalpha(p[3]) ? 9 : 0) + (p[3] & 0xF));
                                p += 4;
                            } else
                                break;
                        }
                        h->udl = o;
                        if (*p)
                            ast_log(LOG_WARNING, "UD too long / invalid UCS-2 hex in %s\n", fn);
                    } else
                        ast_log(LOG_WARNING, "Only ud can use ## format, %s\n", fn);
                } else if (!strcmp(line, "ud")) {       /* user data */
                    int o = 0;
                    while (*p && o < SMSLEN) {
                        if (isxdigit(*p) && isxdigit(p[1])) {
                            h->ud[o++] = (((isalpha(*p) ? 9 : 0) + (*p & 0xF)) << 4) + ((isalpha(p[1]) ? 9 : 0) + (p[1] & 0xF));
                            p += 2;
                        } else {
                            break;
                        }
                    }
                    h->udl = o;
                    if (*p) {
                        ast_log(LOG_WARNING, "UD too long / invalid UCS-1 hex in %s\n", fn);
                    }
                } else if (!strcmp(line, "udh")) {      /* user data header */
                    unsigned char o = 0;
                    h->udhi = 1;
                    while (*p && o < SMSLEN) {
                        if (isxdigit(*p) && isxdigit(p[1])) {
                            h->udh[o] = (((isalpha(*p) ? 9 : 0) + (*p & 0xF)) << 4) + ((isalpha(p[1]) ? 9 : 0) + (p[1] & 0xF));
                            o++;
                            p += 2;
                        } else {
                            break;
                        }
                    }
                    h->udhl = o;
                    if (*p) {
                        ast_log(LOG_WARNING, "UDH too long / invalid hex in %s\n", fn);
                    }
                } else {
                    ast_log(LOG_WARNING, "Only ud and udh can use # format, %s\n", fn);
                }
            } else {
                ast_log(LOG_WARNING, "Cannot parse in %s: %s\n", fn, line);
            }
        }
        fclose(s);
        if (!dcsset && packsms7(0, h->udhl, h->udh, h->udl, h->ud) < 0) {
            if (packsms8(0, h->udhl, h->udh, h->udl, h->ud) < 0) {
                if (packsms16(0, h->udhl, h->udh, h->udl, h->ud) < 0) {
                    ast_log(LOG_WARNING, "Invalid UTF-8 message even for UCS-2 (%s)\n", fn);
                } else {
                    h->dcs = 0x08;          /* default to 16 bit */
                    ast_log(LOG_WARNING, "Sending in 16 bit format(%s)\n", fn);
                }
            } else {
                h->dcs = 0xF5;              /* default to 8 bit */
                ast_log(LOG_WARNING, "Sending in 8 bit format(%s)\n", fn);
            }
        }
        if (is7bit(h->dcs) && packsms7(0, h->udhl, h->udh, h->udl, h->ud) < 0) {
            ast_log(LOG_WARNING, "Invalid 7 bit GSM data %s\n", fn);
        }
        if (is8bit(h->dcs) && packsms8(0, h->udhl, h->udh, h->udl, h->ud) < 0) {
            ast_log(LOG_WARNING, "Invalid 8 bit data %s\n", fn);
        }
        if (is16bit(h->dcs) && packsms16(0, h->udhl, h->udh, h->udl, h->ud) < 0) {
            ast_log(LOG_WARNING, "Invalid 16 bit data %s\n", fn);
        }
    }
}
 
/*! \brief white a received text message to a file */
static void sms_writefile(sms_t * h)
{
    char fn[200] = "", fn2[200] = "";
    char buf[30];
    FILE *o;
 
    if (ast_tvzero(h->scts)) {
        h->scts = ast_tvnow();
    }
    snprintf(fn, sizeof(fn), "%s/sms/%s", ast_config_AST_SPOOL_DIR, h->smsc ? h->rx ? "morx" : "mttx" : h->rx ? "mtrx" : "motx");
    ast_mkdir(fn, 0777);                    /* ensure it exists */
    ast_copy_string(fn2, fn, sizeof(fn2));
    snprintf(fn2 + strlen(fn2), sizeof(fn2) - strlen(fn2), "/%s.%s-%u", h->queue, isodate(h->scts.tv_sec, buf, sizeof(buf)), seq++);
    snprintf(fn + strlen(fn), sizeof(fn) - strlen(fn), "/.%s", fn2 + strlen(fn) + 1);
    if ((o = fopen(fn, "w")) == NULL) {
        return;
    }
 
    if (*h->oa) {
        fprintf(o, "oa=%s\n", h->oa);
    }
    if (*h->da) {
        fprintf(o, "da=%s\n", h->da);
    }
    if (h->udhi) {
        unsigned int p;
        fprintf(o, "udh#");
        for (p = 0; p < h->udhl; p++) {
            fprintf(o, "%02hhX", (unsigned char)h->udh[p]);
        }
        fprintf(o, "\n");
    }
    if (h->udl) {
        unsigned int p;
        for (p = 0; p < h->udl && h->ud[p] >= ' '; p++);
        if (p < h->udl) {
            fputc(';', o);                  /* cannot use ud=, but include as a comment for human readable */
        }
        fprintf(o, "ud=");
        for (p = 0; p < h->udl; p++) {
            unsigned short v = h->ud[p];
            if (v < 32) {
                fputc(191, o);
            } else if (v < 0x80) {
                fputc(v, o);
            } else if (v < 0x800) {
                fputc(0xC0 + (v >> 6), o);
                fputc(0x80 + (v & 0x3F), o);
            } else {
                fputc(0xE0 + (v >> 12), o);
                fputc(0x80 + ((v >> 6) & 0x3F), o);
                fputc(0x80 + (v & 0x3F), o);
            }
        }
        fprintf(o, "\n");
        for (p = 0; p < h->udl && h->ud[p] >= ' '; p++);
        if (p < h->udl) {
            for (p = 0; p < h->udl && h->ud[p] < 0x100; p++);
            if (p == h->udl) {              /* can write in ucs-1 hex */
                fprintf(o, "ud#");
                for (p = 0; p < h->udl; p++) {
                    fprintf(o, "%02hhX", (unsigned char)h->ud[p]);
                }
                fprintf(o, "\n");
            } else {                        /* write in UCS-2 */
                fprintf(o, "ud##");
                for (p = 0; p < h->udl; p++) {
                    fprintf(o, "%04X", (unsigned)h->ud[p]);
                }
                fprintf(o, "\n");
            }
        }
    }
    if (h->scts.tv_sec) {
        char datebuf[30];
        fprintf(o, "scts=%s\n", isodate(h->scts.tv_sec, datebuf, sizeof(datebuf)));
    }
    if (h->pid) {
        fprintf(o, "pid=%d\n", h->pid);
    }
    if (h->dcs != 0xF1) {
        fprintf(o, "dcs=%d\n", h->dcs);
    }
    if (h->vp) {
        fprintf(o, "vp=%u\n", h->vp);
    }
    if (h->srr) {
        fprintf(o, "srr=1\n");
    }
    if (h->mr >= 0) {
        fprintf(o, "mr=%d\n", h->mr);
    }
    if (h->rp) {
        fprintf(o, "rp=1\n");
    }
    fclose(o);
    if (rename(fn, fn2)) {
        unlink(fn);
    } else {
        ast_log(LOG_NOTICE, "Received to %s\n", fn2);
    }
}
 
/*! \brief read dir skipping dot files... */
static struct dirent *readdirqueue(DIR *d, char *queue)
{
    struct dirent *f;
    do {
        f = readdir(d);
    } while (f && (*f->d_name == '.' || strncmp(f->d_name, queue, strlen(queue)) || f->d_name[strlen(queue)] != '.'));
    return f;
}
 
/*! \brief handle the incoming message */
static unsigned char sms_handleincoming (sms_t * h)
{
    unsigned char p = 3;
    if (h->smsc) {                          /* SMSC */
        if ((h->imsg[2] & 3) == 1) {        /* SMS-SUBMIT */
            h->udhl = h->udl = 0;
            h->vp = 0;
            h->srr = ((h->imsg[2] & 0x20) ? 1 : 0);
            h->udhi = ((h->imsg[2] & 0x40) ? 1 : 0);
            h->rp = ((h->imsg[2] & 0x80) ? 1 : 0);
            ast_copy_string(h->oa, h->cli, sizeof(h->oa));
            h->scts = ast_tvnow();
            h->mr = h->imsg[p++];
            p += unpackaddress(h->da, ARRAY_LEN(h->da), h->imsg + p);
            h->pid = h->imsg[p++];
            h->dcs = h->imsg[p++];
            if ((h->imsg[2] & 0x18) == 0x10) {       /* relative VP */
                if (h->imsg[p] < 144) {
                    h->vp = (h->imsg[p] + 1) * 5;
                } else if (h->imsg[p] < 168) {
                    h->vp = 720 + (h->imsg[p] - 143) * 30;
                } else if (h->imsg[p] < 197) {
                    h->vp = (h->imsg[p] - 166) * 1440;
                } else {
                    h->vp = (h->imsg[p] - 192) * 10080;
                }
                p++;
            } else if (h->imsg[2] & 0x18) {
                p += 7;                     /* ignore enhanced / absolute VP */
            }
            p += unpacksms(h->dcs, h->imsg + p, h->udh, ARRAY_LEN(h->udh), &h->udhl, h->ud, ARRAY_LEN(h->ud), &h->udl, h->udhi);
            h->rx = 1;                      /* received message */
            sms_writefile(h);               /* write the file */
            if (p != h->imsg[1] + 2) {
                ast_log(LOG_WARNING, "Mismatch receive unpacking %d/%d\n", p, h->imsg[1] + 2);
                return 0xFF;          /* duh! */
            }
        } else {
            ast_log(LOG_WARNING, "Unknown message type %02hhX\n", h->imsg[2]);
            return 0xFF;
        }
    } else {                                /* client */
        if (!(h->imsg[2] & 3)) {            /* SMS-DELIVER */
            *h->da = h->srr = h->rp = h->vp = h->udhi = h->udhl = h->udl = 0;
            h->srr = ((h->imsg[2] & 0x20) ? 1 : 0);
            h->udhi = ((h->imsg[2] & 0x40) ? 1 : 0);
            h->rp = ((h->imsg[2] & 0x80) ? 1 : 0);
            h->mr = -1;
            p += unpackaddress(h->oa, ARRAY_LEN(h->oa), h->imsg + p);
            h->pid = h->imsg[p++];
            h->dcs = h->imsg[p++];
            h->scts = unpackdate(h->imsg + p);
            p += 7;
            p += unpacksms(h->dcs, h->imsg + p, h->udh, ARRAY_LEN(h->udh), &h->udhl, h->ud, ARRAY_LEN(h->ud), &h->udl, h->udhi);
            h->rx = 1;                      /* received message */
            sms_writefile(h);               /* write the file */
            if (p != h->imsg[1] + 2) {
                ast_log(LOG_WARNING, "Mismatch receive unpacking %d/%d\n", p, h->imsg[1] + 2);
                return 0xFF;                /* duh! */
            }
        } else {
            ast_log(LOG_WARNING, "Unknown message type %02hhX\n", h->imsg[2]);
            return 0xFF;
        }
    }
    return 0;                               /* no error */
}
 
#ifdef SOLARIS
#define NAME_MAX 1024
#endif
 
/*!
 * Add data to a protocol 2 message.
 * Use the length field (h->omsg[1]) as a pointer to the next free position.
 */
static void adddata_proto2(sms_t *h, unsigned char msg, char *data, int size)
{
    int x = h->omsg[1] + 2;                 /* Get current position */
    if (x == 2) {
        x += 2;                             /* First: skip Payload length (set later) */
    }
    h->omsg[x++] = msg;                     /* Message code */
    h->omsg[x++] = (unsigned char)size;     /* Data size Low */
    h->omsg[x++] = 0;                       /* Data size Hi */
    for (; size > 0 ; size--) {
        h->omsg[x++] = *data++;
    }
    h->omsg[1] = x - 2;                     /* Frame size */
    h->omsg[2] = x - 4;                     /* Payload length (Lo) */
    h->omsg[3] = 0;                         /* Payload length (Hi) */
}
 
static void putdummydata_proto2(sms_t *h)
{
    adddata_proto2(h, 0x10, "\0", 1);           /* Media Identifier > SMS */
    adddata_proto2(h, 0x11, "\0\0\0\0\0\0", 6); /* Firmware version */
    adddata_proto2(h, 0x12, "\2\0\4", 3);       /* SMS provider ID */
    adddata_proto2(h, 0x13, h->udtxt, h->udl);  /* Body */
}
 
static void sms_compose2(sms_t *h, int more)
{
    struct ast_tm tm;
    struct timeval now = h->scts;
    char stm[45];
 
    h->omsg[0] = 0x00;                      /* set later... */
    h->omsg[1] = 0;
    putdummydata_proto2(h);
    if (h->smsc) {                          /* deliver */
        h->omsg[0] = 0x11;                  /* SMS_DELIVERY */
        /* Required: 10 11 12 13 14 15 17 (seems they must be ordered!) */
        ast_localtime(&now, &tm, NULL);
        sprintf(stm, "%02d%02d%02d%02d", tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, tm.tm_min);  /* Date mmddHHMM */
        adddata_proto2(h, 0x14, stm, 8);    /* Date */
        if (*h->oa == 0) {
            strcpy(h->oa, "00000000");
        }
        adddata_proto2(h, 0x15, h->oa, strlen(h->oa)); /* Originator */
        adddata_proto2(h, 0x17, "\1", 1);   /* Calling Terminal ID */
    } else {                                /* submit */
        h->omsg[0] = 0x10;                  /* SMS_SUBMIT */
        /* Required: 10 11 12 13 17 18 1B 1C (seems they must be ordered!) */
        adddata_proto2(h, 0x17, "\1", 1);   /* Calling Terminal ID */
        if (*h->da == 0) {
            strcpy(h->da, "00000000");
        }
        adddata_proto2(h, 0x18, h->da, strlen(h->da)); /* Originator */
        adddata_proto2(h, 0x1B, "\1", 1);         /* Called Terminal ID */
        adddata_proto2(h, 0x1C, "\0\0\0", 3);     /* Notification */
    }
}
 
static void putdummydata_proto2(sms_t *h);
 
#define MAX_DEBUG_LEN   300
static char *sms_hexdump(unsigned char buf[], int size, char *s /* destination */)
{
    char *p;
    int f;
 
    for (p = s, f = 0; f < size && f < MAX_DEBUG_LEN; f++, p += 3) {
        sprintf(p, "%02hhX ", (unsigned char)buf[f]);
    }
    return(s);
}
 
 
/*! \brief sms_handleincoming_proto2: handle the incoming message */
static int sms_handleincoming_proto2(sms_t *h)
{
    int f, i, sz = 0;
    int msg, msgsz;
    struct ast_tm tm;
    struct timeval now = { 0, 0 };
    char debug_buf[MAX_DEBUG_LEN * 3 + 1];
 
    sz = h->imsg[1] + 2;
    /* ast_verb(3, "SMS-P2 Frame: %s\n", sms_hexdump(h->imsg, sz, debug_buf)); */
 
    /* Parse message body (called payload) */
    now = h->scts = ast_tvnow();
    for (f = 4; f < sz; ) {
        msg = h->imsg[f++];
        msgsz = h->imsg[f++];
        msgsz += (h->imsg[f++] * 256);
        switch (msg) {
        case 0x13:                          /* Body */
            ast_verb(3, "SMS-P2 Body#%02X=[%.*s]\n", (unsigned)msg, msgsz, &h->imsg[f]);
            if (msgsz >= sizeof(h->ud)) {
                msgsz = sizeof(h->ud) - 1;
            }
            for (i = 0; i < msgsz; i++) {
                h->ud[i] = h->imsg[f + i];
            }
            h->udl = msgsz;
            break;
        case 0x14:                          /* Date SCTS */
            now = h->scts = ast_tvnow();
            ast_localtime(&now, &tm, NULL);
            tm.tm_mon = ( (h->imsg[f] * 10) + h->imsg[f + 1] ) - 1;
            tm.tm_mday = ( (h->imsg[f + 2] * 10) + h->imsg[f + 3] );
            tm.tm_hour = ( (h->imsg[f + 4] * 10) + h->imsg[f + 5] );
            tm.tm_min = ( (h->imsg[f + 6] * 10) + h->imsg[f + 7] );
            tm.tm_sec = 0;
            h->scts = ast_mktime(&tm, NULL);
            ast_verb(3, "SMS-P2 Date#%02X=%02d/%02d %02d:%02d\n", (unsigned)msg, tm.tm_mday, tm.tm_mon + 1, tm.tm_hour, tm.tm_min);
            break;
        case 0x15:                          /* Calling line (from SMSC) */
            if (msgsz >= 20) {
                msgsz = 20 - 1;
            }
            ast_verb(3, "SMS-P2 Origin#%02X=[%.*s]\n", (unsigned)msg, msgsz, &h->imsg[f]);
            ast_copy_string(h->oa, (char *)(&h->imsg[f]), msgsz + 1);
            break;
        case 0x18:                          /* Destination(from TE/phone) */
            if (msgsz >= 20) {
                msgsz = 20 - 1;
            }
            ast_verb(3, "SMS-P2 Destination#%02X=[%.*s]\n", (unsigned)msg, msgsz, &h->imsg[f]);
            ast_copy_string(h->da, (char *)(&h->imsg[f]), msgsz + 1);
            break;
        case 0x1C:                          /* Notify */
            ast_verb(3, "SMS-P2 Notify#%02X=%s\n", (unsigned)msg, sms_hexdump(&h->imsg[f], 3, debug_buf));
            break;
        default:
            ast_verb(3, "SMS-P2 Par#%02X [%d]: %s\n", (unsigned)msg, msgsz, sms_hexdump(&h->imsg[f], msgsz, debug_buf));
            break;
        }
        f+=msgsz;                           /* Skip to next */
    }
    h->rx = 1;                              /* received message */
    sms_writefile(h);                       /* write the file */
    return 0;                               /* no error */
}
 
#if 0
static void smssend(sms_t *h, char *c)
{
    int f, x;
    for (f = 0; f < strlen(c); f++) {
        sscanf(&c[f*3], "%x", &x);
        h->omsg[f] = x;
    }
    sms_messagetx(h);
}
#endif
 
static void sms_nextoutgoing (sms_t *h);
 
static void sms_messagerx2(sms_t * h)
{
    int p = h->imsg[0] & DLL_SMS_MASK ; /* mask the high bit */
    int cause;
 
#define DLL2_ACK(h) ((h->framenumber & 1) ? DLL2_SMS_ACK1: DLL2_SMS_ACK1)
    switch (p) {
    case DLL2_SMS_EST:                      /* Protocol 2: Connection ready (fake): send message  */
        sms_nextoutgoing (h);
        /* smssend(h,"11 29 27 00 10 01 00 00 11 06 00 00 00 00 00 00 00 12 03 00 02 00 04 13 01 00 41 14 08 00 30 39 31 35 30 02 30 02 15 02 00 39 30 "); */
        break;
 
    case DLL2_SMS_INFO_MO:                  /* transport SMS_SUBMIT */
    case DLL2_SMS_INFO_MT:                  /* transport SMS_DELIVERY */
        cause = sms_handleincoming_proto2(h);
        if (!cause) {                       /* ACK */
            sms_log(h, 'Y');
        }
        h->omsg[0] = DLL2_ACK(h);
        h->omsg[1] = 0x06;                  /* msg len */
        h->omsg[2] = 0x04;                  /* payload len */
        h->omsg[3] = 0x00;                  /* payload len */
        h->omsg[4] = 0x1f;                  /* Response type */
        h->omsg[5] = 0x01;                  /* parameter len */
        h->omsg[6] = 0x00;                  /* parameter len */
        h->omsg[7] = cause;                 /* CONFIRM or error */
        sms_messagetx(h);
        break;
 
    case DLL2_SMS_NACK:                     /* Protocol 2: SMS_NAK */
        h->omsg[0] = DLL2_SMS_REL;          /* SMS_REL */
        h->omsg[1] = 0x00;                  /* msg len */
        sms_messagetx(h);
        break;
 
    case DLL2_SMS_ACK0:
    case DLL2_SMS_ACK1:
        /* SMS_ACK also transport SMS_SUBMIT or SMS_DELIVERY */
        if ( (h->omsg[0] & DLL_SMS_MASK) == DLL2_SMS_REL) {
            /* a response to our Release, just hangup */
            h->hangup = 1;                  /* hangup */
        } else {
            /* XXX depending on what we are.. */
            ast_log(LOG_NOTICE, "SMS_SUBMIT or SMS_DELIVERY\n");
            sms_nextoutgoing (h);
        }
        break;
 
    case DLL2_SMS_REL:                      /* Protocol 2: SMS_REL (hangup req) */
        h->omsg[0] = DLL2_ACK(h);
        h->omsg[1] = 0;
        sms_messagetx(h);
        break;
    }
}
 
/*! \brief compose a message for protocol 1 */
static void sms_compose1(sms_t *h, int more)
{
    unsigned int p = 2;                     /* next byte to write. Skip type and len */
 
    h->omsg[0] = 0x91;                      /* SMS_DATA */
    if (h->smsc) {                          /* deliver */
        h->omsg[p++] = (more ? 4 : 0) + ((h->udhl > 0) ? 0x40 : 0);
        p += packaddress(h->omsg + p, h->oa);
        h->omsg[p++] = h->pid;
        h->omsg[p++] = h->dcs;
        packdate(h->omsg + p, h->scts.tv_sec);
        p += 7;
        p += packsms(h->dcs, h->omsg + p, h->udhl, h->udh, h->udl, h->ud);
    } else {                                /* submit */
        h->omsg[p++] =
            0x01 + (more ? 4 : 0) + (h->srr ? 0x20 : 0) + (h->rp ? 0x80 : 0) + (h->vp ? 0x10 : 0) + (h->udhi ? 0x40 : 0);
        if (h->mr < 0) {
            h->mr = message_ref++;
        }
        h->omsg[p++] = h->mr;
        p += packaddress(h->omsg + p, h->da);
        h->omsg[p++] = h->pid;
        h->omsg[p++] = h->dcs;
        if (h->vp) {                        /* relative VP */
            if (h->vp < 720) {
                h->omsg[p++] = (h->vp + 4) / 5 - 1;
            } else if (h->vp < 1440) {
                h->omsg[p++] = (h->vp - 720 + 29) / 30 + 143;
            } else if (h->vp < 43200) {
                h->omsg[p++] = (h->vp + 1439) / 1440 + 166;
            } else if (h->vp < 635040) {
                h->omsg[p++] = (h->vp + 10079) / 10080 + 192;
            } else {
                h->omsg[p++] = 255;         /* max */
            }
        }
        p += packsms(h->dcs, h->omsg + p, h->udhl, h->udh, h->udl, h->ud);
    }
    h->omsg[1] = p - 2;
}
 
/*! \brief find and fill in next message, or send a REL if none waiting */
static void sms_nextoutgoing (sms_t * h)
{
    char fn[100 + NAME_MAX] = "";
    DIR *d;
    char more = 0;
 
    *h->da = *h->oa = '\0';                 /* clear destinations */
    h->rx = 0;                              /* outgoing message */
    snprintf(fn, sizeof(fn), "%s/sms/%s", ast_config_AST_SPOOL_DIR, h->smsc ? "mttx" : "motx");
    ast_mkdir(fn, 0777);                    /* ensure it exists */
    d = opendir(fn);
    if (d) {
        struct dirent *f = readdirqueue(d, h->queue);
        if (f) {
            snprintf(fn + strlen(fn), sizeof(fn) - strlen(fn), "/%s", f->d_name);
            sms_readfile(h, fn);
            if (readdirqueue(d, h->queue)) {
                more = 1;                   /* more to send */
            }
        }
        closedir(d);
    }
    if (*h->da || *h->oa) {                 /* message to send */
        if (h->protocol == 2) {
            sms_compose2(h, more);
        } else {
            sms_compose1(h, more);
        }
    } else {                                /* no message */
        if (h->protocol == 2) {
            h->omsg[0] = 0x17;              /* SMS_REL */
            h->omsg[1] = 0;
            h->sent_rel = 1;
        } else {
            h->omsg[0] = 0x94;              /* SMS_REL */
            h->omsg[1] = 0;
            h->sent_rel = 1;
        }
    }
    sms_messagetx(h);
}
 
#define DIR_RX 1
#define DIR_TX 2
static void sms_debug (int dir, sms_t *h)
{
    char txt[259 * 3 + 1];
    char *p = txt;                          /* always long enough */
    unsigned char *msg = (dir == DIR_RX) ? h->imsg : h->omsg;
    int n = (dir == DIR_RX) ? h->ibytep : msg[1] + 2;
    int q = 0;
    while (q < n && q < 30) {
        sprintf(p, " %02hhX", msg[q++]);
        p += 3;
    }
    if (q < n) {
        sprintf(p, "...");
    }
    ast_verb(3, "SMS %s%s\n", dir == DIR_RX ? "RX" : "TX", txt);
}
 
 
static void sms_messagerx(sms_t * h)
{
    int cause;
 
    sms_debug (DIR_RX, h);
    if (h->protocol == 2) {
        sms_messagerx2(h);
        return;
    }
    /* parse incoming message for Protocol 1 */
    switch (h->imsg[0]) {
    case 0x91:                              /* SMS_DATA */
        cause = sms_handleincoming (h);
        if (!cause) {
            sms_log(h, 'Y');
            h->omsg[0] = 0x95;              /* SMS_ACK */
            h->omsg[1] = 0x02;
            h->omsg[2] = 0x00;              /* deliver report */
            h->omsg[3] = 0x00;              /* no parameters */
        } else {                            /* NACK */
            sms_log(h, 'N');
            h->omsg[0] = 0x96;              /* SMS_NACK */
            h->omsg[1] = 3;
            h->omsg[2] = 0;                 /* delivery report */
            h->omsg[3] = cause;             /* cause */
            h->omsg[4] = 0;                 /* no parameters */
        }
        sms_messagetx(h);
        break;
 
    case 0x92:                              /* SMS_ERROR */
        h->err = 1;
        sms_messagetx(h);                   /* send whatever we sent again */
        break;
    case 0x93:                              /* SMS_EST */
        sms_nextoutgoing (h);
        break;
    case 0x94:                              /* SMS_REL */
        h->hangup = 1;                      /* hangup */
        break;
    case 0x95:                              /* SMS_ACK */
        sms_log(h, 'Y');
        sms_nextoutgoing (h);
        break;
    case 0x96:                              /* SMS_NACK */
        h->err = 1;
        sms_log(h, 'N');
        sms_nextoutgoing (h);
        break;
    default:                                /* Unknown */
        h->omsg[0] = 0x92;                  /* SMS_ERROR */
        h->omsg[1] = 1;
        h->omsg[2] = 3;                     /* unknown message type */
        sms_messagetx(h);
        break;
    }
}
 
static void sms_messagetx(sms_t * h)
{
    unsigned char c = 0, p;
    int len = h->omsg[1] + 2;               /* total message length excluding checksum */
 
    for (p = 0; p < len; p++) {             /* compute checksum */
        c += h->omsg[p];
    }
    h->omsg[len] = 0 - c;                   /* actually, (256 - (c & 0fxx)) & 0xff) */
    sms_debug(DIR_TX, h);
    h->framenumber++;                       /* Proto 2 */
    h->obytep = 0;
    h->obitp = 0;
    if (h->protocol == 2) {                 /* Proto 2: */
        h->oseizure = 300;                  /* 300bits (or more ?) */
        h->obyte = 0;                       /* Seizure starts with  space (0) */
        if (h->omsg[0] == 0x7F) {
            h->opause = 8 * h->opause_0;    /* initial message delay */
        } else {
            h->opause = 400;
        }
    } else {                                /* Proto 1: */
        h->oseizure = 0;                    /* No seizure */
        h->obyte = 1;                       /* send mark ('1') at the beginning */
        /* Change the initial message delay. BT requires 300ms,
         * but for others this might be way too much and the phone
         * could time out. XXX make it configurable.
        */
        if (h->omsg[0] == 0x93) {
            h->opause = 8 * h->opause_0;    /* initial message delay */
        } else {
            h->opause = 200;
        }
    }
    /* Note - setting osync triggers the generator */
    h->osync = OSYNC_BITS;                  /* 80 sync bits */
    h->obyten = len + 1;                    /* bytes to send (including checksum) */
}
 
/*!
 * outgoing data are produced by this generator function, that reads from
 * the descriptor whether it has data to send and which ones.
 */
static int sms_generate(struct ast_channel *chan, void *data, int len, int samples)
{
    struct ast_frame f = { 0 };
#define MAXSAMPLES (800)
    output_t *buf;
    sms_t *h = data;
    int i, res;
 
    if (samples > MAXSAMPLES) {
        ast_log(LOG_WARNING, "Only doing %d samples (%d requested)\n",
             MAXSAMPLES, samples);
        samples = MAXSAMPLES;
    }
    len = samples * sizeof(*buf) + AST_FRIENDLY_OFFSET;
    buf = ast_alloca(len);
 
    f.frametype = AST_FRAME_VOICE;
    f.subclass.format = __OUT_FMT;
    f.datalen = samples * sizeof(*buf);
    f.offset = AST_FRIENDLY_OFFSET;
    f.mallocd = 0;
    f.data.ptr = buf;
    f.samples = samples;
    f.src = "app_sms";
    /* create a buffer containing the digital sms pattern */
    for (i = 0; i < samples; i++) {
        buf[i] = wave_out[0];               /* default is silence */
 
        if (h->opause) {
            h->opause--;
        } else if (h->obyten || h->osync) { /* sending data */
            buf[i] = wave_out[h->ophase];
            h->ophase += (h->obyte & 1) ? 13 : 21; /* compute next phase */
            if (h->ophase >= 80)
                h->ophase -= 80;
            if ((h->ophasep += 12) >= 80) { /* time to send the next bit */
                h->ophasep -= 80;
                if (h->oseizure > 0) {      /* sending channel seizure (proto 2) */
                    h->oseizure--;
                    h->obyte ^= 1;          /* toggle low bit */
                } else if (h->osync) {
                    h->obyte = 1;           /* send mark as sync bit */
                    h->osync--;             /* sending sync bits */
                    if (h->osync == 0 && h->protocol == 2 && h->omsg[0] == DLL2_SMS_EST) {
                        h->obytep = h->obyten = 0; /* we are done */
                    }
                } else {
                    h->obitp++;
                    if (h->obitp == 1) {
                        h->obyte = 0;       /* start bit; */
                    } else if (h->obitp == 2) {
                        h->obyte = h->omsg[h->obytep];
                    } else if (h->obitp == 10) {
                        h->obyte = 1; /* stop bit */
                        h->obitp = 0;
                        h->obytep++;
                        if (h->obytep == h->obyten) {
                            h->obytep = h->obyten = 0; /* sent */
                            h->osync = 10;    /* trailing marks */
                        }
                    } else {
                        h->obyte >>= 1;
                    }
                }
            }
        }
    }
    res = ast_write(chan, &f);
    ast_frfree(&f);
    if (res < 0) {
        ast_log(LOG_WARNING, "Failed to write frame to '%s': %s\n", ast_channel_name(chan), strerror(errno));
        return -1;
    }
    return 0;
#undef MAXSAMPLES
}
 
/*!
 * Just return the pointer to the descriptor that we received.
 */
static void *sms_alloc(struct ast_channel *chan, void *sms_t_ptr)
{
    return sms_t_ptr;
}
 
static void sms_release(struct ast_channel *chan, void *data)
{
    return; /* nothing to do here. */
}
 
static struct ast_generator smsgen = {
    .alloc = sms_alloc,
    .release = sms_release,
    .generate = sms_generate,
};
 
/*!
 * Process an incoming frame, trying to detect the carrier and
 * decode the message. The two frequencies are 1300 and 2100 Hz.
 * The decoder detects the amplitude of the signal over the last
 * few samples, filtering the absolute values with a lowpass filter.
 * If the magnitude (h->imag) is large enough, multiply the signal
 * by the two carriers, and compute the amplitudes m0 and m1.
 * Record the current sample as '0' or '1' depending on which one is greater.
 * The last 3 bits are stored in h->ibith, with the count of '1'
 * bits in h->ibitt.
 * XXX the rest is to be determined.
 */
static void sms_process(sms_t * h, int samples, signed short *data)
{
    int bit;
 
    /*
     * Ignore incoming audio while a packet is being transmitted,
     * the protocol is half-duplex.
     * Unfortunately this means that if the outbound and incoming
     * transmission overlap (which is an error condition anyways),
     * we may miss some data and this makes debugging harder.
     */
    if (h->obyten || h->osync) {
        return;
    }
    for ( ; samples-- ; data++) {
        unsigned long long m0, m1;
        if (abs(*data) > h->imag) {
            h->imag = abs(*data);
        } else {
            h->imag = h->imag * 7 / 8;
        }
        if (h->imag <= 500) {               /* below [arbitrary] threahold: lost carrier */
            if (h->idle++ == 80000) {       /* nothing happening */
                ast_log(LOG_NOTICE, "No data, hanging up\n");
                h->hangup = 1;
                h->err = 1;
            }
            if (h->ierr) {                  /* error */
                ast_log(LOG_NOTICE, "Error %d, hanging up\n", h->ierr);
                /* Protocol 1 */
                h->err = 1;
                h->omsg[0] = 0x92;          /* error */
                h->omsg[1] = 1;
                h->omsg[2] = h->ierr;
                sms_messagetx(h);           /* send error */
            }
            h->ierr = h->ibitn = h->ibytep = h->ibytec = 0;
            continue;
        }
        h->idle = 0;
 
        /* multiply signal by the two carriers. */
        h->ims0 = (h->ims0 * 6 + *data * wave[h->ips0]) / 7;
        h->imc0 = (h->imc0 * 6 + *data * wave[h->ipc0]) / 7;
        h->ims1 = (h->ims1 * 6 + *data * wave[h->ips1]) / 7;
        h->imc1 = (h->imc1 * 6 + *data * wave[h->ipc1]) / 7;
        /* compute the amplitudes */
        m0 = h->ims0 * h->ims0 + h->imc0 * h->imc0;
        m1 = h->ims1 * h->ims1 + h->imc1 * h->imc1;
 
        /* advance the sin/cos pointers */
        if ((h->ips0 += 21) >= 80) {
            h->ips0 -= 80;
        }
        if ((h->ipc0 += 21) >= 80) {
            h->ipc0 -= 80;
        }
        if ((h->ips1 += 13) >= 80) {
            h->ips1 -= 80;
        }
        if ((h->ipc1 += 13) >= 80) {
            h->ipc1 -= 80;
        }
 
        /* set new bit to 1 or 0 depending on which value is stronger */
        h->ibith <<= 1;
        if (m1 > m0) {
            h->ibith |= 1;
        }
        if (h->ibith & 8) {
            h->ibitt--;
        }
        if (h->ibith & 1) {
            h->ibitt++;
        }
        bit = ((h->ibitt > 1) ? 1 : 0);
        if (bit != h->ibitl) {
            h->ibitc = 1;
        } else {
            h->ibitc++;
        }
        h->ibitl = bit;
        if (!h->ibitn && h->ibitc == 4 && !bit) {
            h->ibitn = 1;
            h->iphasep = 0;
        }
        if (bit && h->ibitc == 200) {       /* sync, restart message */
            /* Protocol 2: empty connection ready (I am master) */
            if (h->framenumber <= 0 && h->ibytec >= 160 && !memcmp(h->imsg, "UUUUUUUUUUUUUUUUUUUU", 20)) {
                h->framenumber = 1;
                ast_verb(3, "SMS protocol 2 detected\n");
                h->protocol = 2;
                h->imsg[0] = 0xff;          /* special message (fake) */
                h->imsg[1] = h->imsg[2] = 0x00;
                h->ierr = h->ibitn = h->ibytep = h->ibytec = 0;
                sms_messagerx(h);
            }
            h->ierr = h->ibitn = h->ibytep = h->ibytec = 0;
        }
        if (h->ibitn) {
            h->iphasep += 12;
            if (h->iphasep >= 80) {         /* next bit */
                h->iphasep -= 80;
                if (h->ibitn++ == 9) {      /* end of byte */
                    if (!bit) {             /* bad stop bit */
                        if (h->sent_rel) {
                            h->hangup = 1;
                        } else {
                            ast_log(LOG_NOTICE, "Bad stop bit\n");
                            h->ierr = 0xFF;     /* unknown error */
                        }
                    } else {
                        if (h->ibytep < sizeof(h->imsg)) {
                            h->imsg[h->ibytep] = h->ibytev;
                            h->ibytec += h->ibytev;
                            h->ibytep++;
                        } else if (h->ibytep == sizeof(h->imsg)) {
                            ast_log(LOG_NOTICE, "msg too large\n");
                            h->ierr = 2;    /* bad message length */
                        }
                        if (h->ibytep > 1 && h->ibytep == 3 + h->imsg[1] && !h->ierr) {
                            if (!h->ibytec) {
                                sms_messagerx(h);
                            } else {
                                ast_log(LOG_NOTICE, "bad checksum\n");
                                h->ierr = 1; /* bad checksum */
                            }
                        }
                    }
                    h->ibitn = 0;
                }
                h->ibytev = (h->ibytev >> 1) + (bit ? 0x80 : 0);
            }
        }
    }
}
 
/*
 * Standard argument parsing:
 *  - one enum for the flags we recognise,
 *  - one enum for argument indexes
 *  - AST_APP_OPTIONS() to drive the parsing routine
 *  - in the function, AST_DECLARE_APP_ARGS(...) for the arguments.
 */
enum sms_flags {
    OPTION_BE_SMSC  = (1 << 0),             /* act as sms center */
    OPTION_ANSWER   = (1 << 1),             /* answer on incoming calls */
    OPTION_TWO  = (1 << 2),                 /* Use Protocol Two */
    OPTION_PAUSE    = (1 << 3),             /* pause before sending data, in ms */
    OPTION_SRR  = (1 << 4),                 /* set srr */
    OPTION_DCS  = (1 << 5),                 /* set dcs */
    OPTIONS_NO_LOG  = (1 << 6),             /* Don't log SMS content */
};
 
enum sms_opt_args {
    OPTION_ARG_PAUSE = 0,
    OPTION_ARG_ARRAY_SIZE
};
 
AST_APP_OPTIONS(sms_options, {
    AST_APP_OPTION('s', OPTION_BE_SMSC),
    AST_APP_OPTION('a', OPTION_ANSWER),
    AST_APP_OPTION('t', OPTION_TWO),
    AST_APP_OPTION('r', OPTION_SRR),
    AST_APP_OPTION('o', OPTION_DCS),
    AST_APP_OPTION('n', OPTIONS_NO_LOG),
    AST_APP_OPTION_ARG('p', OPTION_PAUSE, OPTION_ARG_PAUSE),
    } );
 
static int sms_exec(struct ast_channel *chan, const char *data)
{
    int res = -1;
    sms_t h = { 0 };
    /* argument parsing support */
    struct ast_flags flags = { 0 };
    char *parse, *sms_opts[OPTION_ARG_ARRAY_SIZE] = { 0, };
    char *p;
    AST_DECLARE_APP_ARGS(sms_args,
        AST_APP_ARG(queue);
        AST_APP_ARG(options);
        AST_APP_ARG(addr);
        AST_APP_ARG(body);
    );
 
    if (!data) {
        ast_log(LOG_ERROR, "Requires queue name at least\n");
        return -1;
    }
 
    parse = ast_strdupa(data);              /* create a local copy */
    AST_STANDARD_APP_ARGS(sms_args, parse);
    if (sms_args.argc > 1) {
        ast_app_parse_options(sms_options, &flags, sms_opts, sms_args.options);
    }
 
    ast_verb(1, "sms argc %u queue <%s> opts <%s> addr <%s> body <%s>\n",
        sms_args.argc, S_OR(sms_args.queue, ""),
        S_OR(sms_args.options, ""),
        S_OR(sms_args.addr, ""),
        S_OR(sms_args.body, "") );
 
    h.ipc0 = h.ipc1 = 20;                   /* phase for cosine */
    h.dcs = 0xF1;                           /* default */
 
    ast_copy_string(h.cli,
        S_COR(ast_channel_caller(chan)->id.number.valid, ast_channel_caller(chan)->id.number.str, ""),
        sizeof(h.cli));
 
    if (ast_strlen_zero(sms_args.queue)) {
        ast_log(LOG_ERROR, "Requires queue name\n");
        goto done;
    }
    if (strlen(sms_args.queue) >= sizeof(h.queue)) {
        ast_log(LOG_ERROR, "Queue name too long\n");
        goto done;
    }
    ast_copy_string(h.queue, sms_args.queue, sizeof(h.queue));
 
    for (p = h.queue; *p; p++) {
        if (!isalnum(*p)) {
            *p = '-';                       /* make very safe for filenames */
        }
    }
 
    h.smsc = ast_test_flag(&flags, OPTION_BE_SMSC);
    h.protocol = ast_test_flag(&flags, OPTION_TWO) ? 2 : 1;
    h.nolog = ast_test_flag(&flags, OPTIONS_NO_LOG) ? 1 : 0;
    if (!ast_strlen_zero(sms_opts[OPTION_ARG_PAUSE])) {
        h.opause_0 = atoi(sms_opts[OPTION_ARG_PAUSE]);
    }
    if (h.opause_0 < 25 || h.opause_0 > 2000) {
        h.opause_0 = 300;                   /* default 300ms */
    }
    ast_verb(1, "initial delay %dms\n", h.opause_0);
 
 
    /* the following apply if there is an arg3/4 and apply to the created message file */
    if (ast_test_flag(&flags, OPTION_SRR)) {
        h.srr = 1;
    }
    if (ast_test_flag(&flags, OPTION_DCS)) {
        h.dcs = 1;
    }
#if 0
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':                           /* set the pid for saved local message */
            h.pid = 0x40 + (*d & 0xF);
            break;
        }
#endif
    if (sms_args.argc > 2) {
        unsigned char *up;
 
        /* submitting a message, not taking call. */
        /* deprecated, use smsq instead */
        h.scts = ast_tvnow();
        if (ast_strlen_zero(sms_args.addr) || strlen(sms_args.addr) >= sizeof(h.oa)) {
            ast_log(LOG_ERROR, "Address too long %s\n", sms_args.addr);
            goto done;
        }
        if (h.smsc) {
            ast_copy_string(h.oa, sms_args.addr, sizeof(h.oa));
        } else {
            ast_copy_string(h.da, sms_args.addr, sizeof(h.da));
            ast_copy_string(h.oa, h.cli, sizeof(h.oa));
        }
        h.udl = 0;
        if (ast_strlen_zero(sms_args.body)) {
            ast_log(LOG_ERROR, "Missing body for %s\n", sms_args.addr);
            goto done;
        }
        up = (unsigned char *)sms_args.body;
        while (*up && h.udl < SMSLEN) {
            h.ud[h.udl++] = utf8decode(&up);
        }
        if (is7bit(h.dcs) && packsms7(0, h.udhl, h.udh, h.udl, h.ud) < 0) {
            ast_log(LOG_WARNING, "Invalid 7 bit GSM data\n");
            goto done;
        }
        if (is8bit(h.dcs) && packsms8(0, h.udhl, h.udh, h.udl, h.ud) < 0) {
            ast_log(LOG_WARNING, "Invalid 8 bit data\n");
            goto done;
        }
        if (is16bit(h.dcs) && packsms16(0, h.udhl, h.udh, h.udl, h.ud) < 0) {
            ast_log(LOG_WARNING, "Invalid 16 bit data\n");
            goto done;
        }
        h.rx = 0;                           /* sent message */
        h.mr = -1;
        sms_writefile(&h);
        res = h.err;
        goto done;
    }
 
    if (ast_channel_state(chan) != AST_STATE_UP) {      /* make sure channel is answered before any TX */
        ast_answer(chan);
    }
 
    if (ast_test_flag(&flags, OPTION_ANSWER)) {
        h.framenumber = 1;                  /* Proto 2 */
        /* set up SMS_EST initial message */
        if (h.protocol == 2) {
            h.omsg[0] = DLL2_SMS_EST;
            h.omsg[1] = 0;
        } else {
            h.omsg[0] = DLL1_SMS_EST | DLL1_SMS_COMPLETE;
            h.omsg[1] = 0;
        }
        sms_messagetx(&h);
    }
 
    res = ast_set_write_format(chan, __OUT_FMT);
    if (res >= 0) {
        res = ast_set_read_format(chan, ast_format_slin);
    }
    if (res < 0) {
        ast_log(LOG_ERROR, "Unable to set to linear mode, giving up\n");
        goto done;
    }
 
    if ( (res = ast_activate_generator(chan, &smsgen, &h)) < 0) {
        ast_log(LOG_ERROR, "Failed to activate generator on '%s'\n", ast_channel_name(chan));
        goto done;
    }
 
    /* Do our thing here */
    for (;;) {
        struct ast_frame *f;
        int i = ast_waitfor(chan, -1);
        if (i < 0) {
            ast_log(LOG_NOTICE, "waitfor failed\n");
            break;
        }
        if (h.hangup) {
            ast_log(LOG_NOTICE, "channel hangup\n");
            break;
        }
        f = ast_read(chan);
        if (!f) {
            ast_log(LOG_NOTICE, "ast_read failed\n");
            break;
        }
        if (f->frametype == AST_FRAME_VOICE) {
            sms_process(&h, f->samples, f->data.ptr);
        }
 
        ast_frfree(f);
    }
    res = h.err;                            /* XXX */
 
    /*
     * The SMS generator data is on the stack.  We _MUST_ make sure the generator
     * is stopped before returning from this function.
     */
    ast_deactivate_generator(chan);
 
    sms_log(&h, '?');                       /* log incomplete message */
done:
    return (res);
}
 
static int unload_module(void)
{
    return ast_unregister_application(app);
}
 
static int load_module(void)
{
#ifdef OUTALAW
    int p;
    for (p = 0; p < 80; p++) {
        wavea[p] = AST_LIN2A(wave[p]);
    }
#endif
    snprintf(log_file, sizeof(log_file), "%s/sms", ast_config_AST_LOG_DIR);
    return ast_register_application_xml(app, sms_exec);
}
 
AST_MODULE_INFO_STANDARD_EXTENDED(ASTERISK_GPL_KEY, "SMS/PSTN handler");