From 760515c551723fe14f650194f6f4f5ac049b1b8c Mon Sep 17 00:00:00 2001
From: veclavtalica <veclavtalica@tutamail.com>
Date: Wed, 15 Jan 2025 04:36:00 +0300
Subject: [PATCH] minor optimization of strncmp for literal comparison

---
 src/twn_audio.c | 20 +++++++++++---------
 src/twn_loop.c  | 11 ++++++-----
 2 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/src/twn_audio.c b/src/twn_audio.c
index 1dc93a1..53d236a 100644
--- a/src/twn_audio.c
+++ b/src/twn_audio.c
@@ -22,6 +22,12 @@ static const char *audio_exts[AUDIO_FILE_TYPE_COUNT] = {
     ".xm",  /* AUDIO_FILE_TYPE_XM */
 };
 
+static const uint8_t audio_exts_len[AUDIO_FILE_TYPE_COUNT] = {
+    sizeof ".ogg" - 1,
+    sizeof ".wav" - 1,
+    sizeof ".xm" - 1,
+};
+
 /* TODO: allow for vectorization and packed vectors (alignment care and alike) */
 
 /* TODO: count frames without use, free the memory when threshold is met */
@@ -59,14 +65,10 @@ static int64_t get_audio_data(const char *path, unsigned char **data) {
 
 
 static AudioFileType infer_audio_file_type(const char *path) {
-    size_t path_len = SDL_strlen(path);
+    size_t const path_len = SDL_strlen(path);
 
     for (int i = 0; i < AUDIO_FILE_TYPE_COUNT; ++i) {
-        size_t ext_length = SDL_strlen(audio_exts[i]);
-        if (path_len <= ext_length)
-            continue;
-
-        if (SDL_strcmp(&path[path_len - ext_length], audio_exts[i]) == 0)
+        if (SDL_strncmp(&path[path_len - audio_exts_len[i]], audio_exts[i], audio_exts_len[i]) == 0)
             return (AudioFileType)i;
     }
 
@@ -297,17 +299,17 @@ TWN_API void audio_parameter(const char *channel, const char *param, float value
         return;
     }
 
-    if (SDL_strcmp(param, "repeat") == 0) {
+    if (SDL_strncmp(param, "repeat", sizeof "repeat" - 1) == 0) {
         pair->value.repeat = (bool)value;
 
-    } else if (SDL_strcmp(param, "volume") == 0) {
+    } else if (SDL_strncmp(param, "volume", sizeof "volume" - 1) == 0) {
         if (value > 1.0f || value < 0.0f) {
             log_warn("Out of range volume for channel %s set", channel);
             value = clampf(value, 0.0f, 1.0f);
         }
         pair->value.volume = value;
 
-    } else if (SDL_strcmp(param, "panning") == 0) {
+    } else if (SDL_strncmp(param, "panning", sizeof "panning" - 1) == 0) {
         if (value > 1.0f || value < -1.0f) {
             log_warn("Out of range panning for channel %s set", channel);
             value = clampf(value, -1.0f, +1.0f);
diff --git a/src/twn_loop.c b/src/twn_loop.c
index 62d7da0..c16fdcd 100644
--- a/src/twn_loop.c
+++ b/src/twn_loop.c
@@ -215,6 +215,7 @@ static void main_loop(void) {
         game_object_tick();
         input_state_update_postframe(&ctx.input);
 
+        /* TODO: make it works when ctx.ticks_per_second != 60 */
         #ifdef TWN_FEATURE_PUSH_AUDIO
         static uint8_t audio_buffer[(AUDIO_FREQUENCY / 60) * sizeof (float) * 2];
         audio_callback(NULL, audio_buffer, sizeof audio_buffer);
@@ -627,9 +628,9 @@ static bool initialize(void) {
         if (!datum_font_filtering.ok) {
             ctx.font_filtering = TEXT_FONT_FILTERING_DEFAULT;
         } else {
-            if (SDL_strcmp(datum_font_filtering.u.s, "nearest") == 0) {
+            if (SDL_strncmp(datum_font_filtering.u.s, "nearest", sizeof "nearest") == 0) {
                 ctx.font_filtering = TEXTURE_FILTER_NEAREAST;
-            } else if (SDL_strcmp(datum_font_filtering.u.s, "linear") == 0) {
+            } else if (SDL_strncmp(datum_font_filtering.u.s, "linear", sizeof "nearest") == 0) {
                 ctx.font_filtering = TEXTURE_FILTER_LINEAR;
             } else {
                 ctx.font_filtering = TEXT_FONT_FILTERING_DEFAULT;
@@ -727,7 +728,7 @@ int enter_loop(int argc, char **argv) {
 
     for (int i = 1; i < argc; ++i) {
         /* override data directory */
-        if (SDL_strcmp(argv[i], "--data-dir") == 0) {
+        if (SDL_strncmp(argv[i], "--data-dir", sizeof "--data-dir" - 1) == 0) {
             if (argv[i+1] == NULL || SDL_strncmp(argv[i+1], "--", 2) == 0) {
                 CRY("Data dir mount override failed.", "No arguments passed (expected 1).");
                 return EXIT_FAILURE;
@@ -744,13 +745,13 @@ int enter_loop(int argc, char **argv) {
         }
 
         /* force debug mode */
-        if (SDL_strcmp(argv[i], "--debug") == 0) {
+        if (SDL_strncmp(argv[i], "--debug", sizeof "--debug" - 1) == 0) {
             force_debug = true;
             continue;
         }
 
         /* force release mode */
-        if (SDL_strcmp(argv[i], "--release") == 0) {
+        if (SDL_strncmp(argv[i], "--release", sizeof "--release" - 1) == 0) {
             force_release = false;
             continue;
         }