Clean up and ensure proper usage of alloca()

This replaces all calls to alloca() with ast_alloca() which calls gcc's
__builtin_alloca() to avoid BSD semantics and removes all NULL checks
on memory allocated via ast_alloca() and ast_strdupa().

(closes issue ASTERISK-20125)
Review: https://reviewboard.asterisk.org/r/2032/
Patch-by: Walter Doekes (wdoekes)
........

Merged revisions 370642 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 370643 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@370655 65c4cc65-6c06-0410-ace0-fbb531ad65f3

9 files changed, 42 insertions, 44 deletions

diff --git a/channels/chan_alsa.c b/channels/chan_alsa.c
index e535a3adc..71d51adf4 100644
--- a/channels/chan_alsa.c
+++ b/channels/chan_alsa.c
@@ -182,7 +182,7 @@ static snd_pcm_t *alsa_card_init(char *dev, snd_pcm_stream_t stream)
 		ast_debug(1, "Opening device %s in %s mode\n", dev, (stream == SND_PCM_STREAM_CAPTURE) ? "read" : "write");
 	}
 
-	hwparams = alloca(snd_pcm_hw_params_sizeof());
+	hwparams = ast_alloca(snd_pcm_hw_params_sizeof());
 	memset(hwparams, 0, snd_pcm_hw_params_sizeof());
 	snd_pcm_hw_params_any(handle, hwparams);
 
@@ -223,7 +223,7 @@ static snd_pcm_t *alsa_card_init(char *dev, snd_pcm_stream_t stream)
 	if (err < 0)
 		ast_log(LOG_ERROR, "Couldn't set the new hw params: %s\n", snd_strerror(err));
 
-	swparams = alloca(snd_pcm_sw_params_sizeof());
+	swparams = ast_alloca(snd_pcm_sw_params_sizeof());
 	memset(swparams, 0, snd_pcm_sw_params_sizeof());
 	snd_pcm_sw_params_current(handle, swparams);
 
diff --git a/channels/chan_dahdi.c b/channels/chan_dahdi.c
index 28212e5ee..c0afc576a 100644
--- a/channels/chan_dahdi.c
+++ b/channels/chan_dahdi.c
@@ -4181,7 +4181,7 @@ static void dahdi_r2_on_call_disconnect(openr2_chan_t *r2chan, openr2_call_disco
 
 	snprintf(cause_str, sizeof(cause_str), "R2 DISCONNECT (%s)", openr2_proto_get_disconnect_string(cause));
 	datalen += strlen(cause_str);
-	cause_code = alloca(datalen);
+	cause_code = ast_alloca(datalen);
 	cause_code->ast_cause = dahdi_r2_cause_to_ast_cause(cause);
 	ast_copy_string(cause_code->chan_name, ast_channel_name(p->owner), AST_CHANNEL_NAME);
 	ast_copy_string(cause_code->code, cause_str, datalen + 1 - sizeof(*cause_code));
diff --git a/channels/chan_gtalk.c b/channels/chan_gtalk.c
index e1d3ab491..9864f7884 100644
--- a/channels/chan_gtalk.c
+++ b/channels/chan_gtalk.c
@@ -1908,15 +1908,17 @@ static struct ast_channel *gtalk_request(const char *type, struct ast_format_cap
 
 	if (data) {
 		s = ast_strdupa(data);
-		if (s) {
-			sender = strsep(&s, "/");
-			if (sender && (sender[0] != '\0')) {
-				to = strsep(&s, "/");
-			}
-			if (!to) {
-				ast_log(LOG_ERROR, "Bad arguments in Gtalk Dialstring: %s\n", data);
-				return NULL;
-			}
+		sender = strsep(&s, "/");
+		if (sender && (sender[0] != '\0')) {
+			to = strsep(&s, "/");
+		}
+		if (!to) {
+			ast_log(LOG_ERROR, "Bad arguments in Gtalk Dialstring: %s\n", data);
+			return NULL;
+		}
+		if (!to) {
+			ast_log(LOG_ERROR, "Bad arguments in Gtalk Dialstring: %s\n", (char*) data);
+			return NULL;
 		}
 	}
 
diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index 70318a14c..51e777cd0 100644
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -3084,10 +3084,7 @@ static int try_firmware(char *s)
 	unsigned char sum[16], buf[1024];
 	char *s2, *last;
 
-	if (!(s2 = alloca(strlen(s) + 100))) {
-		ast_log(LOG_WARNING, "Alloca failed!\n");
-		return -1;
-	}
+	s2 = ast_alloca(strlen(s) + 100);
 
 	last = strrchr(s, '/');
 	if (last)
@@ -6340,7 +6337,7 @@ static int decode_frame(ast_aes_decrypt_key *dcx, struct ast_iax2_full_hdr *fh,
 	int padding;
 	unsigned char *workspace;
 
-	workspace = alloca(*datalen);
+	workspace = ast_alloca(*datalen);
 	memset(f, 0, sizeof(*f));
 	if (ntohs(fh->scallno) & IAX_FLAG_FULL) {
 		struct ast_iax2_full_enc_hdr *efh = (struct ast_iax2_full_enc_hdr *)fh;
@@ -6386,9 +6383,7 @@ static int encrypt_frame(ast_aes_encrypt_key *ecx, struct ast_iax2_full_hdr *fh,
 {
 	int padding;
 	unsigned char *workspace;
-	workspace = alloca(*datalen + 32);
-	if (!workspace)
-		return -1;
+	workspace = ast_alloca(*datalen + 32);
 	if (ntohs(fh->scallno) & IAX_FLAG_FULL) {
 		struct ast_iax2_full_enc_hdr *efh = (struct ast_iax2_full_enc_hdr *)fh;
 		if (iaxdebug)
@@ -10016,9 +10011,9 @@ static int socket_process_helper(struct iax2_thread *thread)
 	char *using_prefs = "mine";
 
 	/* allocate an iax_frame with 4096 bytes of data buffer */
-	fr = alloca(sizeof(*fr) + 4096);
+	fr = ast_alloca(sizeof(*fr) + 4096);
 	memset(fr, 0, sizeof(*fr));
-	fr->afdatalen = 4096; /* From alloca() above */
+	fr->afdatalen = 4096; /* From ast_alloca() above */
 
 	/* Copy frequently used parameters to the stack */
 	res = thread->buf_len;
@@ -10236,7 +10231,7 @@ static int socket_process_helper(struct iax2_thread *thread)
 		/* add length of subclass */
 		data_size += strlen(subclass);
 
-		cause_code = alloca(data_size);
+		cause_code = ast_alloca(data_size);
 		ast_copy_string(cause_code->chan_name, ast_channel_name(iaxs[fr->callno]->owner), AST_CHANNEL_NAME);
 
 		cause_code->ast_cause = ies.causecode;
@@ -12470,9 +12465,7 @@ static int peer_set_srcaddr(struct iax2_peer *peer, const char *srcaddr)
 	char *host;
 	char *portstr;
 
-	if (!(tmp = ast_strdupa(srcaddr)))
-		return -1;
-
+	tmp = ast_strdupa(srcaddr);
 	ast_sockaddr_split_hostport(tmp, &host, &portstr, 0);
 
 	if (portstr) {
@@ -12935,7 +12928,7 @@ static struct iax2_user *build_user(const char *name, struct ast_variable *v, st
 				ast_append_acl(v->name, v->value, &user->acl, NULL, &subscribe_acl_change);
 			} else if (!strcasecmp(v->name, "setvar")) {
 				varname = ast_strdupa(v->value);
-				if (varname && (varval = strchr(varname,'='))) {
+				if ((varval = strchr(varname, '='))) {
 					*varval = '\0';
 					varval++;
 					if((tmpvar = ast_variable_new(varname, varval, ""))) {
diff --git a/channels/chan_jingle.c b/channels/chan_jingle.c
index 4f4af23fc..a3adb653a 100644
--- a/channels/chan_jingle.c
+++ b/channels/chan_jingle.c
@@ -1553,14 +1553,16 @@ static struct ast_channel *jingle_request(const char *type, struct ast_format_ca
 
 	if (data) {
 		s = ast_strdupa(data);
-		if (s) {
-			sender = strsep(&s, "/");
-			if (sender && (sender[0] != '\0'))
-				to = strsep(&s, "/");
-			if (!to) {
-				ast_log(LOG_ERROR, "Bad arguments in Jingle Dialstring: %s\n", data);
-				return NULL;
-			}
+		sender = strsep(&s, "/");
+		if (sender && (sender[0] != '\0'))
+			to = strsep(&s, "/");
+		if (!to) {
+			ast_log(LOG_ERROR, "Bad arguments in Jingle Dialstring: %s\n", data);
+			return NULL;
+		}
+		if (!to) {
+			ast_log(LOG_ERROR, "Bad arguments in Jingle Dialstring: %s\n", (char*) data);
+			return NULL;
 		}
 	}
 
diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 6c2ff43fd..367aeee8e 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -5657,7 +5657,7 @@ static int create_addr_from_peer(struct sip_pvt *dialog, struct sip_peer *peer)
 
 				/* Change the dialog callid. */
 				callid_size = strlen(tmpcall) + strlen(peer->fromdomain) + 2;
-				new_callid = alloca(callid_size);
+				new_callid = ast_alloca(callid_size);
 				snprintf(new_callid, callid_size, "%s@%s", tmpcall, peer->fromdomain);
 				change_callid_pvt(dialog, new_callid);
 			}
@@ -13829,7 +13829,7 @@ static void state_notify_build_xml(struct state_notify_data *data, int full, con
 					cid_num = S_COR(ast_channel_caller(caller)->id.number.valid,
 						ast_channel_caller(caller)->id.number.str, "");
 					need = strlen(cid_num) + strlen(p->fromdomain) + sizeof("sip:@");
-					remote_target = alloca(need);
+					remote_target = ast_alloca(need);
 					snprintf(remote_target, need, "sip:%s@%s", cid_num, p->fromdomain);
 
 					remote_display = ast_strdupa(S_COR(ast_channel_caller(caller)->id.name.valid,
@@ -13838,7 +13838,7 @@ static void state_notify_build_xml(struct state_notify_data *data, int full, con
 					connected_num = S_COR(ast_channel_connected(caller)->id.number.valid,
 						ast_channel_connected(caller)->id.number.str, "");
 					need = strlen(connected_num) + strlen(p->fromdomain) + sizeof("sip:@");
-					local_target = alloca(need);
+					local_target = ast_alloca(need);
 					snprintf(local_target, need, "sip:%s@%s", connected_num, p->fromdomain);
 
 					local_display = ast_strdupa(S_COR(ast_channel_connected(caller)->id.name.valid,
@@ -25025,7 +25025,8 @@ static int local_attended_transfer(struct sip_pvt *transferer, struct sip_dual *
 			payload_size = ast_connected_line_build_data(connected_line_data,
 				sizeof(connected_line_data), &connected_to_target, NULL);
 			frame_size = payload_size + sizeof(*frame_payload);
-			if (payload_size != -1 && (frame_payload = alloca(frame_size))) {
+			if (payload_size != -1) {
+				frame_payload = ast_alloca(frame_size);
 				frame_payload->payload_size = payload_size;
 				memcpy(frame_payload->payload, connected_line_data, payload_size);
 				frame_payload->action = AST_FRAME_READ_ACTION_CONNECTED_LINE_MACRO;
@@ -27037,7 +27038,7 @@ static int handle_incoming(struct sip_pvt *p, struct sip_request *req, struct as
 				int data_size = sizeof(*cause_code);
 				/* size of the string making up the cause code is "SIP " + cause length */
 				data_size += 4 + strlen(REQ_OFFSET_TO_STR(req, rlpart2));
-				cause_code = alloca(data_size);
+				cause_code = ast_alloca(data_size);
 
 				ast_copy_string(cause_code->chan_name, ast_channel_name(p->owner), AST_CHANNEL_NAME);
 
@@ -31734,7 +31735,7 @@ static int sip_addheader(struct ast_channel *chan, const char *data)
 	}
 	if (ok) {
 		size_t len = strlen(inbuf);
-		subbuf = alloca(len + 1);
+		subbuf = ast_alloca(len + 1);
 		ast_get_encoded_str(inbuf, subbuf, len + 1);
 		pbx_builtin_setvar_helper(chan, varbuf, subbuf);
 		if (sipdebug) {
diff --git a/channels/sig_analog.c b/channels/sig_analog.c
index 608f82b27..2b81eb460 100644
--- a/channels/sig_analog.c
+++ b/channels/sig_analog.c
@@ -2734,7 +2734,7 @@ static struct ast_frame *__analog_handle_event(struct analog_pvt *p, struct ast_
 		data_size += 7;
 		subclass = analog_event2str(res);
 		data_size += strlen(subclass);
-		cause_code = alloca(data_size);
+		cause_code = ast_alloca(data_size);
 		cause_code->ast_cause = AST_CAUSE_NORMAL_CLEARING;
 		ast_copy_string(cause_code->chan_name, ast_channel_name(ast), AST_CHANNEL_NAME);
 		snprintf(cause_code->code, data_size - sizeof(*cause_code) + 1, "ANALOG %s", subclass);
diff --git a/channels/sig_pri.c b/channels/sig_pri.c
index 30d11e755..4bb4066e7 100644
--- a/channels/sig_pri.c
+++ b/channels/sig_pri.c
@@ -1286,7 +1286,7 @@ static void pri_queue_pvt_cause_data(struct sig_pri_span *pri, int chanpos, cons
 	chan = pri->pvts[chanpos]->owner;
 	if (chan) {
 		int datalen = sizeof(*cause_code) + strlen(cause);
-		cause_code = alloca(datalen);
+		cause_code = ast_alloca(datalen);
 		cause_code->ast_cause = ast_cause;
 		ast_copy_string(cause_code->chan_name, ast_channel_name(chan), AST_CHANNEL_NAME);
 		ast_copy_string(cause_code->code, cause, datalen + 1 - sizeof(*cause_code));
diff --git a/channels/sig_ss7.c b/channels/sig_ss7.c
index 810a0d5f2..1e4e7f308 100644
--- a/channels/sig_ss7.c
+++ b/channels/sig_ss7.c
@@ -389,7 +389,7 @@ static void ss7_queue_pvt_cause_data(struct ast_channel *owner, const char *caus
 	struct ast_control_pvt_cause_code *cause_code;
 	int datalen = sizeof(*cause_code) + strlen(cause);
 
-	cause_code = alloca(datalen);
+	cause_code = ast_alloca(datalen);
 	cause_code->ast_cause = ast_cause;
 	ast_copy_string(cause_code->chan_name, ast_channel_name(owner), AST_CHANNEL_NAME);
 	ast_copy_string(cause_code->code, cause, datalen + 1 - sizeof(*cause_code));