make Local channel return sensible device state values

[asterisk-bristuff.git] / file.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * 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 Generic File Format Support.
 *
 * \author Mark Spencer <markster@digium.com> 
 */

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <dirent.h>
#include <sys/types.h>
#include <sys/stat.h>

#include "asterisk/frame.h"
#include "asterisk/file.h"
#include "asterisk/cli.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/sched.h"
#include "asterisk/options.h"
#include "asterisk/translate.h"
#include "asterisk/utils.h"
#include "asterisk/lock.h"
#include "asterisk/app.h"
#include "asterisk/pbx.h"
#include "asterisk/linkedlists.h"
#define MOD_LOADER
#include "asterisk/module.h"

/*
 * The following variable controls the layout of localized sound files.
 * If 0, use the historical layout with prefix just before the filename
 * (i.e. digits/en/1.gsm , digits/it/1.gsm or default to digits/1.gsm),
 * if 1 put the prefix at the beginning of the filename
 * (i.e. en/digits/1.gsm, it/digits/1.gsm or default to digits/1.gsm).
 * The latter permits a language to be entirely in one directory.
 */
int ast_language_is_prefix;

static AST_LIST_HEAD_STATIC(formats, ast_format);

int ast_format_register(const struct ast_format *f)
{
        struct ast_format *tmp;

        if (f->module == NULL) {
                ast_log(LOG_WARNING, "Missing module pointer, you need to supply one\n");
                return -1;
        }
        if (AST_LIST_LOCK(&formats)) {
                ast_log(LOG_WARNING, "Unable to lock format list\n");
                return -1;
        }
        AST_LIST_TRAVERSE(&formats, tmp, list) {
                if (!strcasecmp(f->name, tmp->name)) {
                        AST_LIST_UNLOCK(&formats);
                        ast_log(LOG_WARNING, "Tried to register '%s' format, already registered\n", f->name);
                        return -1;
                }
        }
        tmp = ast_calloc(1, sizeof(struct ast_format));
        if (!tmp) {
                AST_LIST_UNLOCK(&formats);
                return -1;
        }
        *tmp = *f;
        if (tmp->buf_size) {
                /*
                 * Align buf_size properly, rounding up to the machine-specific
                 * alignment for pointers.
                 */
                struct _test_align { void *a, *b; } p;
                int align = (char *)&p.b - (char *)&p.a;
                tmp->buf_size = ((f->buf_size + align - 1)/align)*align;
        }
        
        memset(&tmp->list, 0, sizeof(tmp->list));

        AST_LIST_INSERT_HEAD(&formats, tmp, list);
        AST_LIST_UNLOCK(&formats);
        if (option_verbose > 1)
                ast_verbose( VERBOSE_PREFIX_2 "Registered file format %s, extension(s) %s\n", f->name, f->exts);
        return 0;
}

int ast_format_unregister(const char *name)
{
        struct ast_format *tmp;
        int res = -1;

        if (AST_LIST_LOCK(&formats)) {
                ast_log(LOG_WARNING, "Unable to lock format list\n");
                return -1;
        }
        AST_LIST_TRAVERSE_SAFE_BEGIN(&formats, tmp, list) {
                if (!strcasecmp(name, tmp->name)) {
                        AST_LIST_REMOVE_CURRENT(&formats, list);
                        free(tmp);
                        res = 0;
                }
        }
        AST_LIST_TRAVERSE_SAFE_END
        AST_LIST_UNLOCK(&formats);

        if (!res) {
                if (option_verbose > 1)
                        ast_verbose( VERBOSE_PREFIX_2 "Unregistered format %s\n", name);
        } else
                ast_log(LOG_WARNING, "Tried to unregister format %s, already unregistered\n", name);

        return res;
}

int ast_stopstream(struct ast_channel *tmp)
{
        /* Stop a running stream if there is one */
        if (tmp->stream) {
                ast_closestream(tmp->stream);
                tmp->stream = NULL;
                if (tmp->oldwriteformat && ast_set_write_format(tmp, tmp->oldwriteformat))
                        ast_log(LOG_WARNING, "Unable to restore format back to %d\n", tmp->oldwriteformat);
        }
        return 0;
}

int ast_writestream(struct ast_filestream *fs, struct ast_frame *f)
{
        int res = -1;
        int alt = 0;
        if (f->frametype == AST_FRAME_VIDEO) {
                if (fs->fmt->format < AST_FORMAT_MAX_AUDIO) {
                        /* This is the audio portion.  Call the video one... */
                        if (!fs->vfs && fs->filename) {
                                const char *type = ast_getformatname(f->subclass & ~0x1);
                                fs->vfs = ast_writefile(fs->filename, type, NULL, fs->flags, 0, fs->mode);
                                ast_log(LOG_DEBUG, "Opened video output file\n");
                        }
                        if (fs->vfs)
                                return ast_writestream(fs->vfs, f);
                        /* else ignore */
                        return 0;                               
                } else {
                        /* Might / might not have mark set */
                        alt = 1;
                }
        } else if (f->frametype != AST_FRAME_VOICE) {
                ast_log(LOG_WARNING, "Tried to write non-voice frame\n");
                return -1;
        }
        if (((fs->fmt->format | alt) & f->subclass) == f->subclass) {
                res =  fs->fmt->write(fs, f);
                if (res < 0) 
                        ast_log(LOG_WARNING, "Natural write failed\n");
                else if (res > 0)
                        ast_log(LOG_WARNING, "Huh??\n");
        } else {
                /* XXX If they try to send us a type of frame that isn't the normal frame, and isn't
                       the one we've setup a translator for, we do the "wrong thing" XXX */
                if (fs->trans && f->subclass != fs->lastwriteformat) {
                        ast_translator_free_path(fs->trans);
                        fs->trans = NULL;
                }
                if (!fs->trans) 
                        fs->trans = ast_translator_build_path(fs->fmt->format, f->subclass);
                if (!fs->trans)
                        ast_log(LOG_WARNING, "Unable to translate to format %s, source format %s\n",
                                fs->fmt->name, ast_getformatname(f->subclass));
                else {
                        struct ast_frame *trf;
                        fs->lastwriteformat = f->subclass;
                        /* Get the translated frame but don't consume the original in case they're using it on another stream */
                        trf = ast_translate(fs->trans, f, 0);
                        if (trf) {
                                res = fs->fmt->write(fs, trf);
                                if (res) 
                                        ast_log(LOG_WARNING, "Translated frame write failed\n");
                        } else
                                res = 0;
                }
        }
        return res;
}

static int copy(const char *infile, const char *outfile)
{
        int ifd, ofd, len;
        char buf[4096]; /* XXX make it lerger. */

        if ((ifd = open(infile, O_RDONLY)) < 0) {
                ast_log(LOG_WARNING, "Unable to open %s in read-only mode\n", infile);
                return -1;
        }
        if ((ofd = open(outfile, O_WRONLY | O_TRUNC | O_CREAT, 0600)) < 0) {
                ast_log(LOG_WARNING, "Unable to open %s in write-only mode\n", outfile);
                close(ifd);
                return -1;
        }
        while ( (len = read(ifd, buf, sizeof(buf)) ) ) {
                int res;
                if (len < 0) {
                        ast_log(LOG_WARNING, "Read failed on %s: %s\n", infile, strerror(errno));
                        break;
                }
                /* XXX handle partial writes */
                res = write(ofd, buf, len);
                if (res != len) {
                        ast_log(LOG_WARNING, "Write failed on %s (%d of %d): %s\n", outfile, res, len, strerror(errno));
                        len = -1; /* error marker */
                        break;
                }
        }
        close(ifd);
        close(ofd);
        if (len < 0) {
                unlink(outfile);
                return -1; /* error */
        }
        return 0;       /* success */
}

/*!
 * \brief construct a filename. Absolute pathnames are preserved,
 * relative names are prefixed by the sounds/ directory.
 * The wav49 suffix is replaced by 'WAV'.
 * Returns a malloc'ed string to be freed by the caller.
 */
static char *build_filename(const char *filename, const char *ext)
{
        char *fn = NULL;

        if (!strcmp(ext, "wav49"))
                ext = "WAV";

        if (filename[0] == '/')
                asprintf(&fn, "%s.%s", filename, ext);
        else
                asprintf(&fn, "%s/sounds/%s.%s",
                        ast_config_AST_DATA_DIR, filename, ext);
        return fn;
}

/* compare type against the list 'exts' */
/* XXX need a better algorithm */
static int exts_compare(const char *exts, const char *type)
{
        char tmp[256];
        char *stringp = tmp, *ext;

        ast_copy_string(tmp, exts, sizeof(tmp));
        while ((ext = strsep(&stringp, "|"))) {
                if (!strcmp(ext, type))
                        return 1;
        }

        return 0;
}

static struct ast_filestream *get_filestream(struct ast_format *fmt, FILE *bfile)
{
        struct ast_filestream *s;

        int l = sizeof(*s) + fmt->buf_size + fmt->desc_size;    /* total allocation size */
        if ( (s = ast_calloc(1, l)) == NULL)
                return NULL;
        s->fmt = fmt;
        s->f = bfile;

        if (fmt->desc_size)
                s->private = ((char *)(s+1)) + fmt->buf_size;
        if (fmt->buf_size)
                s->buf = (char *)(s+1);
        s->fr.src = fmt->name;
        return s;
}

/*
 * Default implementations of open and rewrite.
 * Only use them if you don't have expensive stuff to do.
 */
enum wrap_fn { WRAP_OPEN, WRAP_REWRITE };

static int fn_wrapper(struct ast_filestream *s, const char *comment, enum wrap_fn mode)
{
        struct ast_format *f = s->fmt;
        int ret = -1;

        if (mode == WRAP_OPEN && f->open && f->open(s))
                ast_log(LOG_WARNING, "Unable to open format %s\n", f->name);
        else if (mode == WRAP_REWRITE && f->rewrite && f->rewrite(s, comment))
                ast_log(LOG_WARNING, "Unable to rewrite format %s\n", f->name);
        else {
                /* preliminary checks succeed. update usecount */
                ast_atomic_fetchadd_int(&f->module->usecnt, +1);
                ret = 0;
                ast_update_use_count();
        }
        return ret;
}

static int rewrite_wrapper(struct ast_filestream *s, const char *comment)
{
        return fn_wrapper(s, comment, WRAP_REWRITE);
}
                
static int open_wrapper(struct ast_filestream *s)
{
        return fn_wrapper(s, NULL, WRAP_OPEN);
}

enum file_action {
        ACTION_EXISTS = 1, /* return matching format if file exists, 0 otherwise */
        ACTION_DELETE,  /* delete file, return 0 on success, -1 on error */
        ACTION_RENAME,  /* rename file. return 0 on success, -1 on error */
        ACTION_OPEN,
        ACTION_COPY     /* copy file. return 0 on success, -1 on error */
};

/*!
 * \brief perform various actions on a file. Second argument
 * arg2 depends on the command:
 *      unused for EXISTS and DELETE
 *      destination file name (const char *) for COPY and RENAME
 *      struct ast_channel * for OPEN
 * if fmt is NULL, OPEN will return the first matching entry,
 * whereas other functions will run on all matching entries.
 */
static int ast_filehelper(const char *filename, const void *arg2, const char *fmt, const enum file_action action)
{
        struct ast_format *f;
        int res = (action == ACTION_EXISTS) ? 0 : -1;

        if (AST_LIST_LOCK(&formats)) {
                ast_log(LOG_WARNING, "Unable to lock format list\n");
                return res;
        }
        /* Check for a specific format */
        AST_LIST_TRAVERSE(&formats, f, list) {
                char *stringp, *ext = NULL;

                if (fmt && !exts_compare(f->exts, fmt))
                        continue;

                /* Look for a file matching the supported extensions.
                 * The file must exist, and for OPEN, must match
                 * one of the formats supported by the channel.
                 */
                stringp = ast_strdupa(f->exts); /* this is in the stack so does not need to be freed */
                while ( (ext = strsep(&stringp, "|")) ) {
                        struct stat st;
                        char *fn = build_filename(filename, ext);

                        if (fn == NULL)
                                continue;

                        if ( stat(fn, &st) ) { /* file not existent */
                                free(fn);
                                continue;
                        }
                        /* for 'OPEN' we need to be sure that the format matches
                         * what the channel can process
                         */
                        if (action == ACTION_OPEN) {
                                struct ast_channel *chan = (struct ast_channel *)arg2;
                                FILE *bfile;
                                struct ast_filestream *s;

                                if ( !(chan->writeformat & f->format) &&
                                     !(f->format >= AST_FORMAT_MAX_AUDIO && fmt)) {
                                        free(fn);
                                        continue;       /* not a supported format */
                                }
                                if ( (bfile = fopen(fn, "r")) == NULL) {
                                        free(fn);
                                        continue;       /* cannot open file */
                                }
                                s = get_filestream(f, bfile);
                                if (!s) {
                                        fclose(bfile);
                                        free(fn);       /* cannot allocate descriptor */
                                        continue;
                                }
                                if (open_wrapper(s)) {
                                        fclose(bfile);
                                        free(fn);
                                        free(s);
                                        continue;       /* cannot run open on file */
                                }
                                /* ok this is good for OPEN */
                                res = 1;        /* found */
                                s->lasttimeout = -1;
                                s->fmt = f;
                                s->trans = NULL;
                                s->filename = NULL;
                                if (s->fmt->format < AST_FORMAT_MAX_AUDIO)
                                        chan->stream = s;
                                else
                                        chan->vstream = s;
                                break;
                        }
                        switch (action) {
                        case ACTION_OPEN:
                                break;  /* will never get here */

                        case ACTION_EXISTS:     /* return the matching format */
                                res |= f->format;
                                break;

                        case ACTION_DELETE:
                                if ( (res = unlink(fn)) )
                                        ast_log(LOG_WARNING, "unlink(%s) failed: %s\n", fn, strerror(errno));
                                break;

                        case ACTION_RENAME:
                        case ACTION_COPY: {
                                char *nfn = build_filename((const char *)arg2, ext);
                                if (!nfn)
                                        ast_log(LOG_WARNING, "Out of memory\n");
                                else {
                                        res = action == ACTION_COPY ? copy(fn, nfn) : rename(fn, nfn);
                                        if (res)
                                                ast_log(LOG_WARNING, "%s(%s,%s) failed: %s\n",
                                                        action == ACTION_COPY ? "copy" : "rename",
                                                         fn, nfn, strerror(errno));
                                        free(nfn);
                                }
                            }
                                break;

                        default:
                                ast_log(LOG_WARNING, "Unknown helper %d\n", action);
                        }
                        free(fn);
                }
        }
        AST_LIST_UNLOCK(&formats);
        return res;
}

/*!
 * \brief helper routine to locate a file with a given format
 * and language preference.
 * Try preflang, preflang with stripped '_' suffix, or NULL.
 * In the standard asterisk, language goes just before the last component.
 * In an alternative configuration, the language should be a prefix
 * to the actual filename.
 *
 * The last parameter(s) point to a buffer of sufficient size,
 * which on success is filled with the matching filename.
 */
static int fileexists_core(const char *filename, const char *fmt, const char *preflang,
                char *buf, int buflen)
{
        int res = -1;
        int langlen;    /* length of language string */
        const char *c = strrchr(filename, '/');
        int offset = c ? c - filename + 1 : 0;  /* points right after the last '/' */

        if (preflang == NULL)
                preflang = "";
        langlen = strlen(preflang);
        
        if (buflen < langlen + strlen(filename) + 2) {
                ast_log(LOG_WARNING, "buffer too small\n");
                buf[0] = '\0'; /* set to empty */
                buf = alloca(langlen + strlen(filename) + 2);   /* room for everything */
        }
        if (buf == NULL)
                return 0;
        buf[0] = '\0';
        for (;;) {
                if (ast_language_is_prefix) { /* new layout */
                        if (langlen) {
                                strcpy(buf, preflang);
                                buf[langlen] = '/';
                                strcpy(buf + langlen + 1, filename);
                        } else
                                strcpy(buf, filename);  /* first copy the full string */
                } else { /* old layout */
                        strcpy(buf, filename);  /* first copy the full string */
                        if (langlen) {
                                /* insert the language and suffix if needed */
                                strcpy(buf + offset, preflang);
                                sprintf(buf + offset + langlen, "/%s", filename + offset);
                        }
                }
                res = ast_filehelper(buf, NULL, fmt, ACTION_EXISTS);
                if (res > 0)            /* found format */
                        break;
                if (langlen == 0)       /* no more formats */
                        break;
                if (preflang[langlen] == '_') /* we are on the local suffix */
                        langlen = 0;    /* try again with no language */
                else
                        langlen = (c = strchr(preflang, '_')) ? c - preflang : 0;
        }
        return res;
}

struct ast_filestream *ast_openstream(struct ast_channel *chan, const char *filename, const char *preflang)
{
        return ast_openstream_full(chan, filename, preflang, 0);
}

struct ast_filestream *ast_openstream_full(struct ast_channel *chan, const char *filename, const char *preflang, int asis)
{
        /* 
         * Use fileexists_core() to find a file in a compatible
         * language and format, set up a suitable translator,
         * and open the stream.
         */
        int fmts, res, buflen;
        char *buf;

        if (!asis) {
                /* do this first, otherwise we detect the wrong writeformat */
                ast_stopstream(chan);
                if (chan->generator)
                        ast_deactivate_generator(chan);
        }
        if (preflang == NULL)
                preflang = "";
        buflen = strlen(preflang) + strlen(filename) + 2;
        buf = alloca(buflen);
        if (buf == NULL)
                return NULL;
        fmts = fileexists_core(filename, NULL, preflang, buf, buflen);
        if (fmts > 0)
                fmts &= AST_FORMAT_AUDIO_MASK;
        if (fmts < 1) {
                ast_log(LOG_WARNING, "File %s does not exist in any format\n", filename);
                return NULL;
        }
        chan->oldwriteformat = chan->writeformat;
        /* Set the channel to a format we can work with */
        res = ast_set_write_format(chan, fmts);
        res = ast_filehelper(buf, chan, NULL, ACTION_OPEN);
        if (res >= 0)
                return chan->stream;
        return NULL;
}

struct ast_filestream *ast_openvstream(struct ast_channel *chan, const char *filename, const char *preflang)
{
        /* As above, but for video. But here we don't have translators
         * so we must enforce a format.
         */
        unsigned int format;
        char *buf;
        int buflen;

        if (preflang == NULL)
                preflang = "";
        buflen = strlen(preflang) + strlen(filename) + 2;
        buf = alloca(buflen);
        if (buf == NULL)
                return NULL;

        for (format = AST_FORMAT_MAX_AUDIO << 1; format <= AST_FORMAT_MAX_VIDEO; format = format << 1) {
                int fd;
                const char *fmt;

                if (!(chan->nativeformats & format))
                        continue;
                fmt = ast_getformatname(format);
                if ( fileexists_core(filename, fmt, preflang, buf, buflen) < 1) /* no valid format */
                        continue;
                fd = ast_filehelper(buf, chan, fmt, ACTION_OPEN);
                if (fd >= 0)
                        return chan->vstream;
                ast_log(LOG_WARNING, "File %s has video but couldn't be opened\n", filename);
        }
        return NULL;
}

struct ast_frame *ast_readframe(struct ast_filestream *s)
{
        struct ast_frame *f = NULL;
        int whennext = 0;       
        if (s && s->fmt)
                f = s->fmt->read(s, &whennext);
        return f;
}

static int ast_readaudio_callback(void *data)
{
        struct ast_filestream *s = data;
        int whennext = 0;

        while(!whennext) {
                struct ast_frame *fr = s->fmt->read(s, &whennext);
                if (!fr /* stream complete */ || ast_write(s->owner, fr) /* error writing */) {
                        if (fr)
                                ast_log(LOG_WARNING, "Failed to write frame\n");
                        s->owner->streamid = -1;
#ifdef HAVE_ZAPTEL
                        ast_settimeout(s->owner, 0, NULL, NULL);
#endif                  
                        return 0;
                }
        }
        if (whennext != s->lasttimeout) {
#ifdef HAVE_ZAPTEL
                if (s->owner->timingfd > -1)
                        ast_settimeout(s->owner, whennext, ast_readaudio_callback, s);
                else
#endif          
                        s->owner->streamid = ast_sched_add(s->owner->sched, whennext/8, ast_readaudio_callback, s);
                s->lasttimeout = whennext;
                return 0;
        }
        return 1;
}

static int ast_readvideo_callback(void *data)
{
        struct ast_filestream *s = data;
        int whennext = 0;

        while (!whennext) {
                struct ast_frame *fr = s->fmt->read(s, &whennext);
                if (!fr || ast_write(s->owner, fr)) { /* no stream or error, as above */
                        if (fr)
                                ast_log(LOG_WARNING, "Failed to write frame\n");
                        s->owner->vstreamid = -1;
                        return 0;
                }
        }
        if (whennext != s->lasttimeout) {
                s->owner->vstreamid = ast_sched_add(s->owner->sched, whennext/8, ast_readvideo_callback, s);
                s->lasttimeout = whennext;
                return 0;
        }
        return 1;
}

int ast_applystream(struct ast_channel *chan, struct ast_filestream *s)
{
        s->owner = chan;
        return 0;
}

int ast_playstream(struct ast_filestream *s)
{
        if (s->fmt->format < AST_FORMAT_MAX_AUDIO)
                ast_readaudio_callback(s);
        else
                ast_readvideo_callback(s);
        return 0;
}

int ast_seekstream(struct ast_filestream *fs, off_t sample_offset, int whence)
{
        return fs->fmt->seek(fs, sample_offset, whence);
}

int ast_truncstream(struct ast_filestream *fs)
{
        return fs->fmt->trunc(fs);
}

off_t ast_tellstream(struct ast_filestream *fs)
{
        return fs->fmt->tell(fs);
}

int ast_stream_fastforward(struct ast_filestream *fs, off_t ms)
{
        return ast_seekstream(fs, ms * DEFAULT_SAMPLES_PER_MS, SEEK_CUR);
}

int ast_stream_rewind(struct ast_filestream *fs, off_t ms)
{
        return ast_seekstream(fs, -ms * DEFAULT_SAMPLES_PER_MS, SEEK_CUR);
}

int ast_closestream(struct ast_filestream *f)
{
        char *cmd = NULL;
        size_t size = 0;
        /* Stop a running stream if there is one */
        if (f->owner) {
                if (f->fmt->format < AST_FORMAT_MAX_AUDIO) {
                        f->owner->stream = NULL;
                        if (f->owner->streamid > -1)
                                ast_sched_del(f->owner->sched, f->owner->streamid);
                        f->owner->streamid = -1;
#ifdef HAVE_ZAPTEL
                        ast_settimeout(f->owner, 0, NULL, NULL);
#endif                  
                } else {
                        f->owner->vstream = NULL;
                        if (f->owner->vstreamid > -1)
                                ast_sched_del(f->owner->sched, f->owner->vstreamid);
                        f->owner->vstreamid = -1;
                }
        }
        /* destroy the translator on exit */
        if (f->trans)
                ast_translator_free_path(f->trans);

        if (f->realfilename && f->filename) {
                        size = strlen(f->filename) + strlen(f->realfilename) + 15;
                        cmd = alloca(size);
                        memset(cmd,0,size);
                        snprintf(cmd,size,"/bin/mv -f %s %s",f->filename,f->realfilename);
                        ast_safe_system(cmd);
        }

        if (f->filename)
                free(f->filename);
        if (f->realfilename)
                free(f->realfilename);
        if (f->fmt->close)
                f->fmt->close(f);
        fclose(f->f);
        if (f->vfs)
                ast_closestream(f->vfs);
        ast_atomic_fetchadd_int(&f->fmt->module->usecnt, -1);
        ast_update_use_count();
        free(f);
        return 0;
}


/*
 * Look the various language-specific places where a file could exist.
 */
int ast_fileexists(const char *filename, const char *fmt, const char *preflang)
{
        char *buf;
        int buflen;

        if (preflang == NULL)
                preflang = "";
        buflen = strlen(preflang) + strlen(filename) + 2;       /* room for everything */
        buf = alloca(buflen);
        if (buf == NULL)
                return 0;
        return fileexists_core(filename, fmt, preflang, buf, buflen);
}

int ast_filedelete(const char *filename, const char *fmt)
{
        return ast_filehelper(filename, NULL, fmt, ACTION_DELETE);
}

int ast_filerename(const char *filename, const char *filename2, const char *fmt)
{
        return ast_filehelper(filename, filename2, fmt, ACTION_RENAME);
}

int ast_filecopy(const char *filename, const char *filename2, const char *fmt)
{
        return ast_filehelper(filename, filename2, fmt, ACTION_COPY);
}

int ast_streamfile(struct ast_channel *chan, const char *filename, const char *preflang)
{
        struct ast_filestream *fs;
        struct ast_filestream *vfs=NULL;
        char fmt[256];

        fs = ast_openstream(chan, filename, preflang);
        if (fs)
                vfs = ast_openvstream(chan, filename, preflang);
        if (vfs)
                ast_log(LOG_DEBUG, "Ooh, found a video stream, too, format %s\n", ast_getformatname(vfs->fmt->format));
        if (fs){
                if (ast_applystream(chan, fs))
                        return -1;
                if (vfs && ast_applystream(chan, vfs))
                        return -1;
                if (ast_playstream(fs))
                        return -1;
                if (vfs && ast_playstream(vfs))
                        return -1;
#if 1
                if (option_verbose > 2)
                        ast_verbose(VERBOSE_PREFIX_3 "Playing '%s' (language '%s')\n", filename, preflang ? preflang : "default");
#endif
                return 0;
        }
        ast_log(LOG_WARNING, "Unable to open %s (format %s): %s\n", filename, ast_getformatname_multiple(fmt, sizeof(fmt), chan->nativeformats), strerror(errno));
        return -1;
}

struct ast_filestream *ast_readfile(const char *filename, const char *type, const char *comment, int flags, int check, mode_t mode)
{
        FILE *bfile;
        struct ast_format *f;
        struct ast_filestream *fs = NULL;
        char *fn;

        if (AST_LIST_LOCK(&formats)) {
                ast_log(LOG_WARNING, "Unable to lock format list\n");
                return NULL;
        }

        AST_LIST_TRAVERSE(&formats, f, list) {
                fs = NULL;
                if (!exts_compare(f->exts, type))
                        continue;

                fn = build_filename(filename, type);
                errno = 0;
                bfile = fopen(fn, "r");
                if (!bfile || (fs = get_filestream(f, bfile)) == NULL ||
                        open_wrapper(fs) ) {
                        ast_log(LOG_WARNING, "Unable to open %s\n", fn);
                        fclose(bfile);
                        free(fn);
                        if (fs)
                                free(fs);
                        continue;
                }
                /* found it */
                fs->trans = NULL;
                fs->fmt = f;
                fs->flags = flags;
                fs->mode = mode;
                fs->filename = strdup(filename);
                fs->vfs = NULL;
                break;
        }

        AST_LIST_UNLOCK(&formats);
        if (!fs) 
                ast_log(LOG_WARNING, "No such format '%s'\n", type);

        return fs;
}

struct ast_filestream *ast_writefile(const char *filename, const char *type, const char *comment, int flags, int check, mode_t mode)
{
        int fd, myflags = 0;
        /* compiler claims this variable can be used before initialization... */
        FILE *bfile = NULL;
        struct ast_format *f;
        struct ast_filestream *fs = NULL;
        char *buf = NULL;
        size_t size = 0;
        int format_found = 0;

        if (AST_LIST_LOCK(&formats)) {
                ast_log(LOG_WARNING, "Unable to lock format list\n");
                return NULL;
        }

        /* set the O_TRUNC flag if and only if there is no O_APPEND specified */
        /* We really can't use O_APPEND as it will break WAV header updates */
        if (flags & O_APPEND) { 
                flags &= ~O_APPEND;
        } else {
                myflags = O_TRUNC;
        }
        
        myflags |= O_WRONLY | O_CREAT;

        /* XXX need to fix this - we should just do the fopen,
         * not open followed by fdopen()
         */
        AST_LIST_TRAVERSE(&formats, f, list) {
                char *fn, *orig_fn = NULL;
                if (fs)
                        break;

                if (!exts_compare(f->exts, type))
                        continue;
                else
                        format_found = 1;

                fn = build_filename(filename, type);
                fd = open(fn, flags | myflags, mode);
                if (fd > -1) {
                        /* fdopen() the resulting file stream */
                        bfile = fdopen(fd, ((flags | myflags) & O_RDWR) ? "w+" : "w");
                        if (!bfile) {
                                ast_log(LOG_WARNING, "Whoa, fdopen failed: %s!\n", strerror(errno));
                                close(fd);
                                fd = -1;
                        }
                }
                
                if (ast_opt_cache_record_files && (fd > -1)) {
                        char *c;

                        fclose(bfile);  /* this also closes fd */
                        /*
                          We touch orig_fn just as a place-holder so other things (like vmail) see the file is there.
                          What we are really doing is writing to record_cache_dir until we are done then we will mv the file into place.
                        */
                        orig_fn = ast_strdupa(fn);
                        for (c = fn; *c; c++)
                                if (*c == '/')
                                        *c = '_';

                        size = strlen(fn) + strlen(record_cache_dir) + 2;
                        buf = alloca(size);
                        strcpy(buf, record_cache_dir);
                        strcat(buf, "/");
                        strcat(buf, fn);
                        free(fn);
                        fn = buf;
                        fd = open(fn, flags | myflags, mode);
                        if (fd > -1) {
                                /* fdopen() the resulting file stream */
                                bfile = fdopen(fd, ((flags | myflags) & O_RDWR) ? "w+" : "w");
                                if (!bfile) {
                                        ast_log(LOG_WARNING, "Whoa, fdopen failed: %s!\n", strerror(errno));
                                        close(fd);
                                        fd = -1;
                                }
                        }
                }
                if (fd > -1) {
                        errno = 0;
                        fs = get_filestream(f, bfile);
                        if (!fs || rewrite_wrapper(fs, comment)) {
                                ast_log(LOG_WARNING, "Unable to rewrite %s\n", fn);
                                close(fd);
                                if (orig_fn) {
                                        unlink(fn);
                                        unlink(orig_fn);
                                }
                                if (fs)
                                        free(fs);
                        }
                        fs->trans = NULL;
                        fs->fmt = f;
                        fs->flags = flags;
                        fs->mode = mode;
                        if (orig_fn) {
                                fs->realfilename = strdup(orig_fn);
                                fs->filename = strdup(fn);
                        } else {
                                fs->realfilename = NULL;
                                fs->filename = strdup(filename);
                        }
                        fs->vfs = NULL;
                        /* If truncated, we'll be at the beginning; if not truncated, then append */
                        f->seek(fs, 0, SEEK_END);
                } else if (errno != EEXIST) {
                        ast_log(LOG_WARNING, "Unable to open file %s: %s\n", fn, strerror(errno));
                        if (orig_fn)
                                unlink(orig_fn);
                }
                /* if buf != NULL then fn is already free and pointing to it */
                if (!buf)
                        free(fn);
        }

        AST_LIST_UNLOCK(&formats);

        if (!format_found)
                ast_log(LOG_WARNING, "No such format '%s'\n", type);

        return fs;
}

/*!
 * \brief the core of all waitstream() functions
 */
static int waitstream_core(struct ast_channel *c, const char *breakon,
        const char *forward, const char *rewind, int skip_ms,
        int audiofd, int cmdfd,  const char *context)
{
        if (!breakon)
                breakon = "";
        if (!forward)
                forward = "";
        if (!rewind)
                rewind = "";
        
        while (c->stream) {
                int res;
                int ms = ast_sched_wait(c->sched);
                if (ms < 0 && !c->timingfunc) {
                        ast_stopstream(c);
                        break;
                }
                if (ms < 0)
                        ms = 1000;
                if (!cmdfd) {
                        res = ast_waitfor(c, ms);
                        if (res < 0) {
                                ast_log(LOG_WARNING, "Select failed (%s)\n", strerror(errno));
                                return res;
                        }
                } else {
                        int outfd;
                        struct ast_channel *rchan = ast_waitfor_nandfds(&c, 1, &cmdfd, (cmdfd > -1) ? 1 : 0, NULL, &outfd, &ms);
                        if (!rchan && (outfd < 0) && (ms)) {
                                /* Continue */
                                if (errno == EINTR)
                                        continue;
                                ast_log(LOG_WARNING, "Wait failed (%s)\n", strerror(errno));
                                return -1;
                        } else if (outfd > -1) { /* this requires cmdfd set */
                                /* The FD we were watching has something waiting */
                                return 1;
                        }
                        /* if rchan is set, it is 'c' */
                        res = rchan ? 1 : 0; /* map into 'res' values */
                }
                if (res > 0) {
                        struct ast_frame *fr = ast_read(c);
                        if (!fr)
                                return -1;
                        switch(fr->frametype) {
                        case AST_FRAME_DTMF:
                                if (context) {
                                        const char exten[2] = { fr->subclass, '\0' };
                                        if (ast_exists_extension(c, context, exten, 1, c->cid.cid_num)) {
                                                ast_frfree(fr);
                                                return res;
                                        }
                                } else {
                                        res = fr->subclass;
                                        if (strchr(forward,res)) {
                                                ast_stream_fastforward(c->stream, skip_ms);
                                        } else if (strchr(rewind,res)) {
                                                ast_stream_rewind(c->stream, skip_ms);
                                        } else if (strchr(breakon, res)) {
                                                ast_frfree(fr);
                                                return res;
                                        }                                       
                                }
                                break;
                        case AST_FRAME_CONTROL:
                                switch(fr->subclass) {
                                case AST_CONTROL_HANGUP:
                                        ast_frfree(fr);
                                        return -1;
                                case AST_CONTROL_RINGING:
                                case AST_CONTROL_ANSWER:
                                case AST_CONTROL_VIDUPDATE:
                                        /* Unimportant */
                                        break;
                                default:
                                        ast_log(LOG_WARNING, "Unexpected control subclass '%d'\n", fr->subclass);
                                }
                        case AST_FRAME_VOICE:
                                /* Write audio if appropriate */
                                if (audiofd > -1)
                                        write(audiofd, fr->data, fr->datalen);
                        }
                        /* Ignore all others */
                        ast_frfree(fr);
                }
                ast_sched_runq(c->sched);
        }
        return (c->_softhangup ? -1 : 0);
}

int ast_waitstream_fr(struct ast_channel *c, const char *breakon, const char *forward, const char *rewind, int ms)
{
        return waitstream_core(c, breakon, forward, rewind, ms,
                -1 /* no audiofd */, -1 /* no cmdfd */, NULL /* no context */);
}

int ast_waitstream(struct ast_channel *c, const char *breakon)
{
        return waitstream_core(c, breakon, NULL, NULL, 0, -1, -1, NULL);
}

int ast_waitstream_full(struct ast_channel *c, const char *breakon, int audiofd, int cmdfd)
{
        return waitstream_core(c, breakon, NULL, NULL, 0,
                audiofd, cmdfd, NULL /* no context */);
}

int ast_waitstream_exten(struct ast_channel *c, const char *context)
{
        /* Waitstream, with return in the case of a valid 1 digit extension */
        /* in the current or specified context being pressed */

        if (!context)
                context = c->context;
        return waitstream_core(c, NULL, NULL, NULL, 0,
                -1, -1, context);
}

/*
 * if the file name is non-empty, try to play it.
 * Return 0 if success, -1 if error, digit if interrupted by a digit.
 * If digits == "" then we can simply check for non-zero.
 */
int ast_stream_and_wait(struct ast_channel *chan, const char *file,
        const char *language, const char *digits)
{
        int res = 0;
        if (!ast_strlen_zero(file)) {
                res =  ast_streamfile(chan, file, language);
                if (!res)
                        res = ast_waitstream(chan, digits);
        }
        return res;
} 

static int show_file_formats(int fd, int argc, char *argv[])
{
#define FORMAT "%-10s %-10s %-20s\n"
#define FORMAT2 "%-10s %-10s %-20s\n"
        struct ast_format *f;
        int count_fmt = 0;

        if (argc != 3)
                return RESULT_SHOWUSAGE;
        ast_cli(fd, FORMAT, "Format", "Name", "Extensions");
                
        if (AST_LIST_LOCK(&formats)) {
                ast_log(LOG_WARNING, "Unable to lock format list\n");
                return -1;
        }

        AST_LIST_TRAVERSE(&formats, f, list) {
                ast_cli(fd, FORMAT2, ast_getformatname(f->format), f->name, f->exts);
                count_fmt++;
        }
        AST_LIST_UNLOCK(&formats);
        ast_cli(fd, "%d file formats registered.\n", count_fmt);
        return RESULT_SUCCESS;
#undef FORMAT
#undef FORMAT2
}

struct ast_cli_entry show_file =
{
        { "show", "file", "formats" },
        show_file_formats,
        "Displays file formats",
        "Usage: show file formats\n"
        "       displays currently registered file formats (if any)\n"
};

int ast_file_init(void)
{
        ast_cli_register(&show_file);
        return 0;
}