Skip to content
Snippets Groups Projects
format_sln.c 5.56 KiB
Newer Older
  • Learn to ignore specific revisions
  • /*
     * Asterisk -- A telephony toolkit for Linux.
     *
     * RAW SLINEAR Format
     * Anthony Minessale (anthmct@yahoo.com)
     * Derived from format_pcm.c in the asterisk distro
     *
     * This program is free software, distributed under the terms of
     * the GNU General Public License
     */
     
    
    #include "asterisk/lock.h"
    #include "asterisk/channel.h"
    #include "asterisk/file.h"
    #include "asterisk/logger.h"
    #include "asterisk/sched.h"
    #include "asterisk/module.h"
    #include "asterisk/endian.h"
    
    #include <netinet/in.h>
    #include <arpa/inet.h>
    #include <stdlib.h>
    #include <sys/time.h>
    #include <stdio.h>
    #include <unistd.h>
    #include <errno.h>
    #include <string.h>
    
    #define BUF_SIZE 320		/* 320 samples */
    
    struct ast_filestream {
    	void *reserved[AST_RESERVED_POINTERS];
    	/* This is what a filestream means to us */
    	int fd; /* Descriptor */
    	struct ast_channel *owner;
    	struct ast_frame fr;				/* Frame information */
    	char waste[AST_FRIENDLY_OFFSET];	/* Buffer for sending frames, etc */
    	char empty;							/* Empty character */
    	unsigned char buf[BUF_SIZE];				/* Output Buffer */
    	struct timeval last;
    };
    
    
    AST_MUTEX_DEFINE_STATIC(slinear_lock);
    static int glistcnt = 0;
    
    static char *name = "sln";
    static char *desc = "Raw Signed Linear Audio support (SLN)";
    static char *exts = "sln|raw";
    
    static struct ast_filestream *slinear_open(int fd)
    {
    	/* We don't have any header to read or anything really, but
    	   if we did, it would go here.  We also might want to check
    	   and be sure it's a valid file.  */
    	struct ast_filestream *tmp;
    	if ((tmp = malloc(sizeof(struct ast_filestream)))) {
    		memset(tmp, 0, sizeof(struct ast_filestream));
    		if (ast_mutex_lock(&slinear_lock)) {
    			ast_log(LOG_WARNING, "Unable to lock slinear list\n");
    			free(tmp);
    			return NULL;
    		}
    		tmp->fd = fd;
    		tmp->fr.data = tmp->buf;
    		tmp->fr.frametype = AST_FRAME_VOICE;
    		tmp->fr.subclass = AST_FORMAT_SLINEAR;
    		/* datalen will vary for each frame */
    		tmp->fr.src = name;
    		tmp->fr.mallocd = 0;
    		glistcnt++;
    		ast_mutex_unlock(&slinear_lock);
    		ast_update_use_count();
    	}
    	return tmp;
    }
    
    
    static struct ast_filestream *slinear_rewrite(int fd, const char *comment)
    
    {
    	/* We don't have any header to read or anything really, but
    	   if we did, it would go here.  We also might want to check
    	   and be sure it's a valid file.  */
    	struct ast_filestream *tmp;
    	if ((tmp = malloc(sizeof(struct ast_filestream)))) {
    		memset(tmp, 0, sizeof(struct ast_filestream));
    		if (ast_mutex_lock(&slinear_lock)) {
    			ast_log(LOG_WARNING, "Unable to lock slinear list\n");
    			free(tmp);
    			return NULL;
    		}
    		tmp->fd = fd;
    		glistcnt++;
    		ast_mutex_unlock(&slinear_lock);
    		ast_update_use_count();
    	} else
    		ast_log(LOG_WARNING, "Out of memory\n");
    	return tmp;
    }
    
    static void slinear_close(struct ast_filestream *s)
    {
    	if (ast_mutex_lock(&slinear_lock)) {
    		ast_log(LOG_WARNING, "Unable to lock slinear list\n");
    		return;
    	}
    	glistcnt--;
    	ast_mutex_unlock(&slinear_lock);
    	ast_update_use_count();
    	close(s->fd);
    	free(s);
    	s = NULL;
    }
    
    static struct ast_frame *slinear_read(struct ast_filestream *s, int *whennext)
    {
    	int res;
    	int delay;
    	/* Send a frame from the file to the appropriate channel */
    
    	s->fr.frametype = AST_FRAME_VOICE;
    	s->fr.subclass = AST_FORMAT_SLINEAR;
    	s->fr.offset = AST_FRIENDLY_OFFSET;
    	s->fr.mallocd = 0;
    	s->fr.data = s->buf;
    	if ((res = read(s->fd, s->buf, BUF_SIZE)) < 1) {
    		if (res)
    			ast_log(LOG_WARNING, "Short read (%d) (%s)!\n", res, strerror(errno));
    		return NULL;
    	}
    	s->fr.samples = res/2;
    	s->fr.datalen = res;
    	delay = s->fr.samples;
    	*whennext = delay;
    	return &s->fr;
    }
    
    static int slinear_write(struct ast_filestream *fs, struct ast_frame *f)
    {
    	int res;
    	if (f->frametype != AST_FRAME_VOICE) {
    		ast_log(LOG_WARNING, "Asked to write non-voice frame!\n");
    		return -1;
    	}
    	if (f->subclass != AST_FORMAT_SLINEAR) {
    		ast_log(LOG_WARNING, "Asked to write non-slinear frame (%d)!\n", f->subclass);
    		return -1;
    	}
    	if ((res = write(fs->fd, f->data, f->datalen)) != f->datalen) {
    			ast_log(LOG_WARNING, "Bad write (%d/%d): %s\n", res, f->datalen, strerror(errno));
    			return -1;
    	}
    	return 0;
    }
    
    static int slinear_seek(struct ast_filestream *fs, long sample_offset, int whence)
    {
    	off_t offset=0,min,cur,max;
    
    	min = 0;
    
    	cur = lseek(fs->fd, 0, SEEK_CUR);
    	max = lseek(fs->fd, 0, SEEK_END);
    	if (whence == SEEK_SET)
    		offset = sample_offset;
    	else if (whence == SEEK_CUR || whence == SEEK_FORCECUR)
    		offset = sample_offset + cur;
    	else if (whence == SEEK_END)
    		offset = max - sample_offset;
    	if (whence != SEEK_FORCECUR) {
    		offset = (offset > max)?max:offset;
    	}
    
    	/* always protect against seeking past begining. */
    
    	offset = (offset < min)?min:offset;
    	return lseek(fs->fd, offset, SEEK_SET);
    }
    
    static int slinear_trunc(struct ast_filestream *fs)
    {
    	return ftruncate(fs->fd, lseek(fs->fd,0,SEEK_CUR));
    }
    
    static long slinear_tell(struct ast_filestream *fs)
    {
    	off_t offset;
    	offset = lseek(fs->fd, 0, SEEK_CUR);
    	return offset;
    }
    
    static char *slinear_getcomment(struct ast_filestream *s)
    {
    	return NULL;
    }
    
    int load_module()
    {
    	return ast_format_register(name, exts, AST_FORMAT_SLINEAR,
    								slinear_open,
    								slinear_rewrite,
    								slinear_write,
    								slinear_seek,
    								slinear_trunc,
    								slinear_tell,
    								slinear_read,
    								slinear_close,
    								slinear_getcomment);
    								
    								
    }
    
    int unload_module()
    {
    	return ast_format_unregister(name);
    }	
    
    int usecount()
    {
    	int res;
    	if (ast_mutex_lock(&slinear_lock)) {
    		ast_log(LOG_WARNING, "Unable to lock slinear list\n");
    		return -1;
    	}
    	res = glistcnt;
    	ast_mutex_unlock(&slinear_lock);
    	return res;
    }
    
    char *description()
    {
    	return desc;
    }
    
    
    char *key()
    {
    	return ASTERISK_GPL_KEY;
    }