From 51b635cc98a5638d22330904c43bd38ad0ae679a Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Wed, 6 May 2026 13:35:09 +0200
Subject: [PATCH] modules: convert snprintf to strbuf

Use spa_strbuf instead of snprintf to handle errors better.
---
 spa/include/spa/debug/mem.h                | 11 +++++++----
 src/modules/module-protocol-native.c       | 10 ++++++----
 src/modules/module-protocol-pulse/module.c |  8 +++++---
 src/modules/module-zeroconf-discover.c     | 12 +++++++-----
 4 files changed, 25 insertions(+), 16 deletions(-)

diff --git a/spa/include/spa/debug/mem.h b/spa/include/spa/debug/mem.h
index 4285225c7..30276268c 100644
--- a/spa/include/spa/debug/mem.h
+++ b/spa/include/spa/debug/mem.h
@@ -8,6 +8,7 @@
 #include <inttypes.h>
 
 #include <spa/debug/context.h>
+#include <spa/utils/string.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -30,13 +31,15 @@ SPA_API_DEBUG_MEM int spa_debugc_mem(struct spa_debug_context *ctx, int indent,
 {
 	const uint8_t *t = (const uint8_t*)data;
 	char buffer[512];
+	struct spa_strbuf b;
 	size_t i;
-	int pos = 0;
 
 	for (i = 0; i < size; i++) {
-		if (i % 16 == 0)
-			pos = snprintf(buffer, sizeof(buffer), "%p: ", &t[i]);
-		pos += snprintf(buffer + pos, sizeof(buffer) - pos, "%02x ", t[i]);
+		if (i % 16 == 0) {
+			spa_strbuf_init(&b, buffer, sizeof(buffer));
+			spa_strbuf_append(&b, "%p: ", &t[i]);
+		}
+		spa_strbuf_append(&b, "%02x ", t[i]);
 		if (i % 16 == 15 || i == size - 1) {
 			spa_debugc(ctx, "%*s" "%s", indent, "", buffer);
 		}
diff --git a/src/modules/module-protocol-native.c b/src/modules/module-protocol-native.c
index 91acfc976..b2e8482c2 100644
--- a/src/modules/module-protocol-native.c
+++ b/src/modules/module-protocol-native.c
@@ -632,13 +632,15 @@ static struct client_data *client_new(struct server *s, int fd)
 			pw_log_warn("server %p: security label error: %m", s);
 	} else {
 		if (!check_print(buffer, len)) {
-			char *hex, *p;
+			char *hex;
+			struct spa_strbuf b;
 			static const char *ch = "0123456789abcdef";
 
-			p = hex = alloca(len * 2 + 10);
-			p += snprintf(p, 5, "hex:");
+			hex = alloca(len * 2 + 10);
+			spa_strbuf_init(&b, hex, len * 2 + 10);
+			spa_strbuf_append(&b, "hex:");
 			for(i = 0; i < (int)len; i++)
-				p += snprintf(p, 3, "%c%c",
+				spa_strbuf_append(&b, "%c%c",
 						ch[buffer[i] >> 4], ch[buffer[i] & 0xf]);
 			pw_properties_set(props, PW_KEY_SEC_LABEL, hex);
 
diff --git a/src/modules/module-protocol-pulse/module.c b/src/modules/module-protocol-pulse/module.c
index 37989985b..3b0cf0ea5 100644
--- a/src/modules/module-protocol-pulse/module.c
+++ b/src/modules/module-protocol-pulse/module.c
@@ -288,13 +288,15 @@ void audioinfo_to_properties(struct spa_audio_info_raw *info, struct pw_properti
 	if (info->rate)
 		pw_properties_setf(props, SPA_KEY_AUDIO_RATE, "%u", info->rate);
 	if (info->channels) {
-		char *s, *p, pos[8];
+		char *s, pos[8];
+		struct spa_strbuf b;
 
 		pw_properties_setf(props, SPA_KEY_AUDIO_CHANNELS, "%u", info->channels);
 
-		p = s = alloca(info->channels * 8);
+		s = alloca(info->channels * 8);
+		spa_strbuf_init(&b, s, info->channels * 8);
 		for (i = 0; i < info->channels; i++)
-			p += spa_scnprintf(p, 8, "%s%s", i == 0 ? "" : ", ",
+			spa_strbuf_append(&b, "%s%s", i == 0 ? "" : ", ",
 				channel_id2name(info->position[i], pos, sizeof(pos)));
 		pw_properties_setf(props, SPA_KEY_AUDIO_POSITION, "[ %s ]", s);
 	}
diff --git a/src/modules/module-zeroconf-discover.c b/src/modules/module-zeroconf-discover.c
index 92f426740..f6f19192a 100644
--- a/src/modules/module-zeroconf-discover.c
+++ b/src/modules/module-zeroconf-discover.c
@@ -184,18 +184,20 @@ static void pw_properties_from_zeroconf(const char *key, const char *value,
 	else if (spa_streq(key, "channel_map")) {
 		struct channel_map channel_map;
 		uint32_t i, pos[CHANNELS_MAX];
-		char *p, *s, buf[8];
+		char *s, buf[8];
 
 		spa_zero(channel_map);
 		channel_map_parse(value, &channel_map);
 		channel_map_to_positions(&channel_map, pos, CHANNELS_MAX);
 
-		p = s = alloca(4 + channel_map.channels * 8);
-		p += spa_scnprintf(p, 2, "[");
+		s = alloca(4 + channel_map.channels * 8);
+		struct spa_strbuf b;
+		spa_strbuf_init(&b, s, 4 + channel_map.channels * 8);
+		spa_strbuf_append(&b, "[");
 		for (i = 0; i < channel_map.channels; i++)
-			p += spa_scnprintf(p, 8, "%s%s", i == 0 ? "" : ",",
+			spa_strbuf_append(&b, "%s%s", i == 0 ? "" : ",",
 				channel_id2name(pos[i], buf, sizeof(buf)));
-		p += spa_scnprintf(p, 2, "]");
+		spa_strbuf_append(&b, "]");
 		pw_properties_set(props, SPA_KEY_AUDIO_POSITION, s);
 	}
 	else if (spa_streq(key, "format")) {