Replaced strncat/strncpy with strlcat/strlcpy

The strncat/strncpy functions have dangerously counter-intuitive
semantics. They are meant to be used with fixed-width,
non-null-terminated strings, which is in, 99% cases, not what you want.

The strlcat/strlcpy ones are non-standard, however SDL provides its own
implementations on platforms that do not have them.

src/dialog.c

@@ -32,7 +32,7 @@ void dadd_msg(Dialog *d, Side side, char *msg) {
 	d->messages = realloc(d->messages, (++d->count)*sizeof(DialogMessage));
 	d->messages[d->count-1].side = side;
 	d->messages[d->count-1].msg = malloc(strlen(msg) + 1);
-	strncpy(d->messages[d->count-1].msg, msg, strlen(msg) + 1);
+	strlcpy(d->messages[d->count-1].msg, msg, strlen(msg) + 1);
 }
 
 void delete_dialog(Dialog *d) {

src/global.h

@@ -166,4 +166,10 @@ enum {
 	EV_CHECK_DESYNC, // replay-only
 };
 
+#define strlcat SDL_strlcat
+#define strlcpy SDL_strlcpy
+
+#define strncat DO_NOT_USE_strncat_USE_strlcat
+#define strncpy DO_NOT_USE_strncpy_USE_strlcpy
+
 #endif

src/menu/charselect.c

@@ -53,7 +53,7 @@ void draw_char_menu(MenuData *menu) {
 	char buf[128];
 	int i;
 	for(i = 0; i < menu->ecount; i++) {
-		strncpy(buf, menu->entries[i].name, sizeof(buf));
+		strlcpy(buf, menu->entries[i].name, sizeof(buf));
 
 		char *tex = strtok(buf,"|");
 		char *name = strtok(NULL, "|");
@@ -84,7 +84,7 @@ void draw_char_menu(MenuData *menu) {
 			glColor4f(1,1,1,1-menu->entries[i].drawdata*3);
 		draw_text(AL_Center, 0, 70, title, _fonts.standard);
 
-		strncpy(buf, mod->entries[i].name, sizeof(buf));
+		strlcpy(buf, mod->entries[i].name, sizeof(buf));
 
 		char *mari = strtok(buf, "|");
 		char *youmu = strtok(NULL, "|");

src/menu/options.c

@@ -15,9 +15,6 @@
 #include "paths/native.h"
 #include "taisei_err.h"
 
-#define strlcat SDL_strlcat
-#define strlcpy SDL_strlcpy
-
 // --- Menu entry <-> config option binding stuff --- //
 
 void bind_init(OptionBinding *bind) {

src/menu/replayview.c

@@ -210,7 +210,7 @@ static void replayview_drawitem(void *n, int item, int cnt) {
 
 			case 1:
 				a = AL_Center;
-				strncpy(tmp, rpy->playername, 128);
+				strlcpy(tmp, rpy->playername, sizeof(tmp));
 				break;
 
 			case 2:

src/menu/savereplay.c

@@ -27,7 +27,7 @@ void save_rpy(void *a) {
 
 	char prepr[16], drepr[16];
 	plrmode_repr(prepr, 16, rpy->stages[0].plr_char, rpy->stages[0].plr_shot);
-	strncpy(drepr, difficulty_name(rpy->stages[0].diff), 16);
+	strlcpy(drepr, difficulty_name(rpy->stages[0].diff), 16);
 	drepr[0] += 'a' - 'A';
 
 	if(rpy->numstages > 1)

src/resource/animation.c

@@ -18,9 +18,9 @@ Animation *init_animation(char *filename) {
 	char *beg = strstr(filename, "gfx/") + 4;
 	char *end = strrchr(filename, '.');
 
-	char *name = malloc(end - beg + 1);
-	memset(name, 0, end - beg + 1);
-	strncpy(name, beg, end-beg);
+	int sz = end - beg + 1;
+	char *name = malloc(sz);
+	strlcpy(name, beg, sz);
 
 	char* tok;
 	strtok(name, "_");

src/resource/audio.c

@@ -131,9 +131,9 @@ Sound *load_sound_or_bgm(char *filename, Sound **dest, const char *res_directory
 	char *beg = strstr(filename, res_directory) + strlen(res_directory);
 	char *end = strrchr(filename, '.');
 
-	snd->name = malloc(end - beg + 1);
-	memset(snd->name, 0, end-beg + 1);
-	strncpy(snd->name, beg, end-beg);
+	int sz = end - beg + 1;
+	snd->name = malloc(sz);
+	strlcpy(snd->name, beg, sz);
 
 	printf("-- loaded '%s' as '%s', type %s\n", filename, snd->name, type);
 

src/resource/model.c

@@ -125,10 +125,9 @@ Model *load_model(char *filename) {
 	char *beg = strstr(filename, "models/") + 7;
 	char *end = strrchr(filename, '.');
 
-	m->name = malloc(end - beg + 1);
-	memset(m->name, 0, end-beg + 1);
-	strncpy(m->name, beg, end-beg);
-
+	int sz = end - beg + 1;
+	m->name = malloc(sz);
+	strlcpy(m->name, beg, sz);
 
 	parse_obj(filename, &data);
 

src/resource/shader.c

@@ -75,8 +75,8 @@ char *copy_segment(char *text, char *delim, int *size) {
 		return NULL;
 
 	*size = end-beg;
-	seg = malloc(*size);
-	strncpy(seg, beg, *size);
+	seg = malloc(*size+1);
+	strlcpy(seg, beg, *size+1);
 
 	return seg;
 }
@@ -135,11 +135,11 @@ void load_shader_snippets(char *filename, char *prefix) {
 			memset(vtext, 0, vhsize + ssize + vfsize + 1);
 			memset(ftext, 0, fhsize + 1);
 
-			strncpy(vtext, vhead, vhsize);
-			strncpy(ftext, fhead, fhsize);
+			strlcpy(vtext, vhead, vhsize+1);
+			strlcpy(ftext, fhead, fhsize+1);
 
-			strncpy(vtext+vhsize, sec, ssize);
-			strncpy(vtext+vhsize+ssize, vfoot, vfsize);
+			strlcpy(vtext+vhsize, sec, ssize+1);
+			strlcpy(vtext+vhsize+ssize, vfoot, vfsize+1);
 
 		} else if(ffoot) {
 			ftext = malloc(fhsize + ssize + ffsize + 1);
@@ -148,19 +148,19 @@ void load_shader_snippets(char *filename, char *prefix) {
 			memset(ftext, 0, fhsize + ssize + ffsize + 1);
 			memset(vtext, 0, vhsize + 1);
 
-			strncpy(ftext, fhead, fhsize);
-			strncpy(vtext, vhead, vhsize);
+			strlcpy(ftext, fhead, fhsize+1);
+			strlcpy(vtext, vhead, vhsize+1);
 
-			strncpy(ftext+fhsize, sec, ssize);
-			strncpy(ftext+fhsize+ssize, ffoot, ffsize);
+			strlcpy(ftext+fhsize, sec, ssize+1);
+			strlcpy(ftext+fhsize+ssize, ffoot, ffsize+1);
 		}
 
 		nbuf = malloc(nend-name+prefixlen+1);
 		strcpy(nbuf, prefix);
-		strncat(nbuf+prefixlen, name, nend-name);
+		strlcat(nbuf+prefixlen, name, nend-name+1);
 		nbuf[nend-name+prefixlen] = 0;
 
-		load_shader(vtext, ftext, nbuf, nend-name+prefixlen);
+		load_shader(vtext, ftext, nbuf, nend-name+prefixlen+1);
 		printf("--- loaded snippet as shader '%s'\n", nbuf);
 
 		free(nbuf);
@@ -195,11 +195,11 @@ void load_shader_file(char *filename) {
 	beg = strstr(filename, "shader/") + 7;
 	end = strrchr(filename, '.');
 
-	name = malloc(end-beg + 1);
-	strncpy(name, beg, end-beg);
-	name[end-beg] = 0;
+	int sz = end - beg + 1;
+	name = malloc(sz);
+	strlcpy(name, beg, sz);
 
-	load_shader(vtext, ftext, name, end-beg);
+	load_shader(vtext, ftext, name, sz);
 
 	printf("-- loaded '%s' as '%s'\n", filename, name);
 
@@ -237,9 +237,8 @@ void load_shader(char *vtext, char *ftext, char *name, int nsize) {
 
 	print_program_info_log(sha->prog);
 
-	sha->name = malloc(nsize + 1);
-	strncpy(sha->name, name, nsize);
-	sha->name[nsize] = 0;
+	sha->name = malloc(nsize);
+	strlcpy(sha->name, name, nsize);
 
 	cache_uniforms(sha);
 }

src/resource/texture.c

@@ -86,9 +86,9 @@ Texture *load_texture(const char *filename) {
 	char *beg = strstr(filename, "gfx/") + 4;
 	char *end = strrchr(filename, '.');
 
-	texture->name = malloc(end - beg + 1);
-	memset(texture->name, 0, end-beg + 1);
-	strncpy(texture->name, beg, end-beg);
+	int sz = end - beg + 1;
+	texture->name = malloc(sz);
+	strlcpy(texture->name, beg, sz);
 
 	printf("-- loaded '%s' as '%s'\n", filename, texture->name);