codec_dahdi: Cannot use struct ast_translator.core_{src,src}_codec.

This fixes a Segmentation fault introduced in r419044 "media formats: re-architect
handling of media for performance improvements".

The problem is that codec_dahdi was using core_src_codec and core_dst_codec in the
ast_translator structure when these fields were never set. Now instead of trying to map
the new core codec descriptions to the way DAHDI defines different codecs, we will store
the DAHDI specific formats in 'struct translator' directly so we can refer to them without
mapping.

This also allows us to remove the "global_format_map" structure, since we can now query
the list of translators directly to make sure we do not ever register a DAHDI based
translator for a specific path more than once and eliminate the need to keep the list and
the map in sync.

ASTERISK-24435 #close
Reported by: Marian Koniuszko

Review: https://reviewboard.asterisk.org/r/4105/
........

Merged revisions 426097 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@426099 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 56 insertions, 135 deletions

diff --git a/codecs/codec_dahdi.c b/codecs/codec_dahdi.c
index 7a49b74ac..8832bc317 100644
--- a/codecs/codec_dahdi.c
+++ b/codecs/codec_dahdi.c
@@ -32,6 +32,7 @@
  ***/
 
 #include "asterisk.h"
+#include <stdbool.h>
 
 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 
@@ -152,71 +153,14 @@ static uint64_t bitfield_dahdi2ast(unsigned dahdi)
 
 /*!
  * \internal
- * \brief Convert old Asterisk format bitfield to DAHDI format bitfield.
+ * \brief Get the ast_codec by DAHDI format.
  * \since 13.0.0
  *
- * \param ast Old Asterisk bitfield to convert.
- *
- * \note They should be the same values but they don't have to be.
- *
- * \return DAHDI bitfield equivalent.
- */
-static unsigned bitfield_ast2dahdi(uint64_t ast)
-{
-	unsigned dahdi;
-
-	switch (ast) {
-	case AST_FORMAT_G723:
-		dahdi = DAHDI_FORMAT_G723_1;
-		break;
-	case AST_FORMAT_GSM:
-		dahdi = DAHDI_FORMAT_GSM;
-		break;
-	case AST_FORMAT_ULAW:
-		dahdi = DAHDI_FORMAT_ULAW;
-		break;
-	case AST_FORMAT_ALAW:
-		dahdi = DAHDI_FORMAT_ALAW;
-		break;
-	case AST_FORMAT_G726_AAL2:
-		dahdi = DAHDI_FORMAT_G726;
-		break;
-	case AST_FORMAT_ADPCM:
-		dahdi = DAHDI_FORMAT_ADPCM;
-		break;
-	case AST_FORMAT_SLIN:
-		dahdi = DAHDI_FORMAT_SLINEAR;
-		break;
-	case AST_FORMAT_LPC10:
-		dahdi = DAHDI_FORMAT_LPC10;
-		break;
-	case AST_FORMAT_G729:
-		dahdi = DAHDI_FORMAT_G729A;
-		break;
-	case AST_FORMAT_SPEEX:
-		dahdi = DAHDI_FORMAT_SPEEX;
-		break;
-	case AST_FORMAT_ILBC:
-		dahdi = DAHDI_FORMAT_ILBC;
-		break;
-	default:
-		dahdi = 0;
-		break;
-	}
-
-	return dahdi;
-}
-
-/*!
- * \internal
- * \brief Get the DAHDI codec by index.
- * \since 13.0.0
- *
- * \param idx Codex index (0-31).
+ * \param dahdi_fmt DAHDI specific codec identifier.
  *
  * \return Specified codec if exists otherwise NULL.
  */
-static const struct ast_codec *get_dahdi_codec(unsigned idx)
+static const struct ast_codec *get_dahdi_codec(uint32_t dahdi_fmt)
 {
 	const struct ast_codec *codec;
 
@@ -276,7 +220,7 @@ static const struct ast_codec *get_dahdi_codec(unsigned idx)
 		.sample_rate = 8000,
 	};
 
-	switch (1UL << idx) {
+	switch (dahdi_fmt) {
 	case DAHDI_FORMAT_G723_1:
 		codec = &dahdi_g723_1;
 		break;
@@ -324,17 +268,18 @@ static struct ast_cli_entry cli[] = {
 	AST_CLI_DEFINE(handle_cli_transcoder_show, "Display DAHDI transcoder utilization.")
 };
 
-struct format_map {
-	unsigned int map[32][32];
-};
-
-static struct format_map global_format_map = { { { 0 } } };
-
 struct translator {
 	struct ast_translator t;
+	uint32_t src_dahdi_fmt;
+	uint32_t dst_dahdi_fmt;
 	AST_LIST_ENTRY(translator) entry;
 };
 
+#ifndef container_of
+#define container_of(ptr, type, member) \
+	((type *)((char *)(ptr) - offsetof(type, member)))
+#endif
+
 static AST_LIST_HEAD_STATIC(translators, translator);
 
 struct codec_dahdi_pvt {
@@ -665,7 +610,7 @@ static struct ast_format *dahdi_format_to_cached(int format)
 	return NULL;
 }
 
-static int dahdi_translate(struct ast_trans_pvt *pvt, struct ast_codec *dst_codec, struct ast_codec *src_codec)
+static int dahdi_translate(struct ast_trans_pvt *pvt, uint32_t dst_dahdi_fmt, uint32_t src_dahdi_fmt)
 {
 	/* Request translation through zap if possible */
 	int fd;
@@ -679,13 +624,13 @@ static int dahdi_translate(struct ast_trans_pvt *pvt, struct ast_codec *dst_code
 		return -1;
 	}
 
-	dahdip->fmts.srcfmt = bitfield_ast2dahdi(ast_format_compatibility_codec2bitfield(src_codec));
-	dahdip->fmts.dstfmt = bitfield_ast2dahdi(ast_format_compatibility_codec2bitfield(dst_codec));
+	dahdip->fmts.srcfmt = src_dahdi_fmt;
+	dahdip->fmts.dstfmt = dst_dahdi_fmt;
 
 	ast_assert(pvt->f.subclass.format == NULL);
 	pvt->f.subclass.format = ao2_bump(dahdi_format_to_cached(dahdip->fmts.dstfmt));
 
-	ast_debug(1, "Opening transcoder channel from %s to %s.\n", src_codec->name, dst_codec->name);
+	ast_debug(1, "Opening transcoder channel from %s to %s.\n", pvt->t->src_codec.name, pvt->t->dst_codec.name);
 
 retry:
 	if (ioctl(fd, DAHDI_TC_ALLOCATE, &dahdip->fmts)) {
@@ -743,9 +688,9 @@ retry:
 
 static int dahdi_new(struct ast_trans_pvt *pvt)
 {
-	return dahdi_translate(pvt,
-		pvt->t->core_dst_codec,
-		pvt->t->core_src_codec);
+	struct translator *zt = container_of(pvt->t, struct translator, t);
+
+	return dahdi_translate(pvt, zt->dst_dahdi_fmt, zt->src_dahdi_fmt);
 }
 
 static struct ast_frame *fakesrc_sample(void)
@@ -760,26 +705,21 @@ static struct ast_frame *fakesrc_sample(void)
 	return &f;
 }
 
-static int is_encoder(struct translator *zt)
+static bool is_encoder(uint32_t src_dahdi_fmt)
 {
-	if ((zt->t.core_src_codec->id == ast_format_get_codec_id(ast_format_ulaw)) ||
-		(zt->t.core_src_codec->id == ast_format_get_codec_id(ast_format_alaw)) ||
-		(zt->t.core_src_codec->id == ast_format_get_codec_id(ast_format_slin))) {
-		return 1;
-	} else {
-		return 0;
-	}
+	return ((src_dahdi_fmt & (DAHDI_FORMAT_ULAW | DAHDI_FORMAT_ALAW | DAHDI_FORMAT_SLINEAR)) > 0);
 }
 
-static int register_translator(unsigned dst, unsigned src)
+/* Must be called with the translators list locked. */
+static int register_translator(uint32_t dst_dahdi_fmt, uint32_t src_dahdi_fmt)
 {
 	const struct ast_codec *dst_codec;
 	const struct ast_codec *src_codec;
 	struct translator *zt;
 	int res;
 
-	dst_codec = get_dahdi_codec(dst);
-	src_codec = get_dahdi_codec(src);
+	dst_codec = get_dahdi_codec(dst_dahdi_fmt);
+	src_codec = get_dahdi_codec(src_dahdi_fmt);
 	if (!dst_codec || !src_codec) {
 		return -1;
 	}
@@ -788,13 +728,16 @@ static int register_translator(unsigned dst, unsigned src)
 		return -1;
 	}
 
+	zt->src_dahdi_fmt = src_dahdi_fmt;
+	zt->dst_dahdi_fmt = dst_dahdi_fmt;
+
 	snprintf(zt->t.name, sizeof(zt->t.name), "dahdi_%s_to_%s",
 		src_codec->name, dst_codec->name);
 
 	memcpy(&zt->t.src_codec, src_codec, sizeof(*src_codec));
 	memcpy(&zt->t.dst_codec, dst_codec, sizeof(*dst_codec));
 	zt->t.buf_size = BUFFER_SIZE;
-	if (is_encoder(zt)) {
+	if (is_encoder(src_dahdi_fmt)) {
 		zt->t.framein = dahdi_encoder_framein;
 		zt->t.frameout = dahdi_encoder_frameout;
 	} else {
@@ -813,79 +756,65 @@ static int register_translator(unsigned dst, unsigned src)
 		return -1;
 	}
 
-	AST_LIST_LOCK(&translators);
 	AST_LIST_INSERT_HEAD(&translators, zt, entry);
-	AST_LIST_UNLOCK(&translators);
-
-	global_format_map.map[dst][src] = 1;
 
 	return res;
 }
 
-static void drop_translator(unsigned dst, unsigned src)
+static void unregister_translators(void)
 {
 	struct translator *cur;
 
 	AST_LIST_LOCK(&translators);
-	AST_LIST_TRAVERSE_SAFE_BEGIN(&translators, cur, entry) {
-		if (bitfield_ast2dahdi(ast_format_compatibility_codec2bitfield(cur->t.core_src_codec))
-			!= (1U << src)) {
-			continue;
-		}
-		if (bitfield_ast2dahdi(ast_format_compatibility_codec2bitfield(cur->t.core_dst_codec))
-			!= (1U << dst)) {
-			continue;
-		}
-
-		AST_LIST_REMOVE_CURRENT(entry);
+	while ((cur = AST_LIST_REMOVE_HEAD(&translators, entry))) {
 		ast_unregister_translator(&cur->t);
 		ast_free(cur);
-		global_format_map.map[dst][src] = 0;
-		break;
 	}
-	AST_LIST_TRAVERSE_SAFE_END;
 	AST_LIST_UNLOCK(&translators);
 }
 
-static void unregister_translators(void)
+/* Must be called with the translators list locked. */
+static bool is_already_registered(uint32_t dstfmt, uint32_t srcfmt)
 {
-	struct translator *cur;
+	bool res = false;
+	const struct translator *zt;
 
-	AST_LIST_LOCK(&translators);
-	while ((cur = AST_LIST_REMOVE_HEAD(&translators, entry))) {
-		ast_unregister_translator(&cur->t);
-		ast_free(cur);
+	AST_LIST_TRAVERSE(&translators, zt, entry) {
+		if ((zt->src_dahdi_fmt == srcfmt) && (zt->dst_dahdi_fmt == dstfmt)) {
+			res = true;
+			break;
+		}
 	}
-	AST_LIST_UNLOCK(&translators);
+
+	return res;
 }
 
-static void build_translators(struct format_map *map, unsigned int dstfmts, unsigned int srcfmts)
+static void build_translators(uint32_t dstfmts, uint32_t srcfmts)
 {
-	unsigned int src, dst;
+	uint32_t srcfmt;
+	uint32_t dstfmt;
 
-	for (src = 0; src < 32; src++) {
-		for (dst = 0; dst < 32; dst++) {
-			if (!(srcfmts & (1 << src)))
-				continue;
+	AST_LIST_LOCK(&translators);
 
-			if (!(dstfmts & (1 << dst)))
+	for (srcfmt = 1; srcfmt != 0; srcfmt <<= 1) {
+		for (dstfmt = 1; dstfmt != 0; dstfmt <<= 1) {
+			if (!(dstfmts & dstfmt) || !(srcfmts & srcfmt)) {
 				continue;
-
-			if (global_format_map.map[dst][src])
+			}
+			if (is_already_registered(dstfmt, srcfmt)) {
 				continue;
-
-			if (!register_translator(dst, src))
-				map->map[dst][src] = 1;
+			}
+			register_translator(dstfmt, srcfmt);
 		}
 	}
+
+	AST_LIST_UNLOCK(&translators);
 }
 
 static int find_transcoders(void)
 {
 	struct dahdi_transcoder_info info = { 0, };
-	struct format_map map = { { { 0 } } };
 	int fd;
-	unsigned int x, y;
 
 	if ((fd = open("/dev/dahdi/transcode", O_RDWR)) < 0) {
 		ast_log(LOG_ERROR, "Failed to open /dev/dahdi/transcode: %s\n", strerror(errno));
@@ -910,9 +839,8 @@ static int find_transcoders(void)
 			info.srcfmts &= ~(DAHDI_FORMAT_ULAW | DAHDI_FORMAT_ALAW);
 		}
 
-		build_translators(&map, info.dstfmts, info.srcfmts);
+		build_translators(info.dstfmts, info.srcfmts);
 		ast_atomic_fetchadd_int(&channels.total, info.numchannels / 2);
-
 	}
 
 	close(fd);
@@ -921,13 +849,6 @@ static int find_transcoders(void)
 		ast_verb(2, "No hardware transcoders found.\n");
 	}
 
-	for (x = 0; x < 32; x++) {
-		for (y = 0; y < 32; y++) {
-			if (!map.map[x][y] && global_format_map.map[x][y])
-				drop_translator(x, y);
-		}
-	}
-
 	return 0;
 }