Improve C++ compatibility a bit

Author: rexim

nob.h

@@ -196,6 +196,12 @@ NOBDEF bool nob_delete_file(const char *path);
 #define NOB_DA_INIT_CAP 256
 #endif
 
+#ifdef __cplusplus
+#define NOB_DECLTYPE_CAST(T) (decltype(T))
+#else
+#define NOB_DECLTYPE_CAST(T)
+#endif // __cplusplus
+
 #define nob_da_reserve(da, expected_capacity)                                              \
     do {                                                                                   \
         if ((expected_capacity) > (da)->capacity) {                                        \
@@ -205,7 +211,7 @@ NOBDEF bool nob_delete_file(const char *path);
             while ((expected_capacity) > (da)->capacity) {                                 \
                 (da)->capacity *= 2;                                                       \
             }                                                                              \
-            (da)->items = NOB_REALLOC((da)->items, (da)->capacity * sizeof(*(da)->items)); \
+            (da)->items = NOB_DECLTYPE_CAST((da)->items)NOB_REALLOC((da)->items, (da)->capacity * sizeof(*(da)->items)); \
             NOB_ASSERT((da)->items != NULL && "Buy more RAM lol");                         \
         }                                                                                  \
     } while (0)
@@ -340,7 +346,7 @@ typedef struct {
 
 NOBDEF bool nob_cmd_run_opt(Nob_Cmd *cmd, Nob_Cmd_Opt opt);
 
-#define nob_cmd_run(cmd, ...) nob_cmd_run_opt((cmd), (Nob_Cmd_Opt){0, __VA_ARGS__ })
+#define nob_cmd_run(cmd, ...) nob_cmd_run_opt((cmd), (Nob_Cmd_Opt){0, __VA_ARGS__})
 
 // DEPRECATED:
 //
@@ -381,7 +387,6 @@ typedef struct {
 // use it as a C string.
 NOBDEF void nob_cmd_render(Nob_Cmd cmd, Nob_String_Builder *render);
 
-// TODO: implement C++ support for nob.h
 #define nob_cmd_append(cmd, ...) \
     nob_da_append_many(cmd, \
                        ((const char*[]){__VA_ARGS__}), \
@@ -836,7 +841,7 @@ NOBDEF bool nob_copy_file(const char *src_path, const char *dst_path)
     int src_fd = -1;
     int dst_fd = -1;
     size_t buf_size = 32*1024;
-    char *buf = NOB_REALLOC(NULL, buf_size);
+    char *buf = (char*)NOB_REALLOC(NULL, buf_size);
     NOB_ASSERT(buf != NULL && "Buy more RAM lol!!");
     bool result = true;
 
@@ -1326,6 +1331,7 @@ NOBDEF bool nob_read_entire_dir(const char *parent, Nob_File_Paths *children)
 {
     bool result = true;
     DIR *dir = NULL;
+    struct dirent *ent = NULL;
 
     dir = opendir(parent);
     if (dir == NULL) {
@@ -1338,7 +1344,7 @@ NOBDEF bool nob_read_entire_dir(const char *parent, Nob_File_Paths *children)
     }
 
     errno = 0;
-    struct dirent *ent = readdir(dir);
+    ent = readdir(dir);
     while (ent != NULL) {
         nob_da_append(children, nob_temp_strdup(ent->d_name));
         ent = readdir(dir);
@@ -1362,6 +1368,7 @@ NOBDEF bool nob_write_entire_file(const char *path, const void *data, size_t siz
 {
     bool result = true;
 
+    const char *buf = NULL;
     FILE *f = fopen(path, "wb");
     if (f == NULL) {
         nob_log(NOB_ERROR, "Could not open file %s for writing: %s\n", path, strerror(errno));
@@ -1374,7 +1381,7 @@ NOBDEF bool nob_write_entire_file(const char *path, const void *data, size_t siz
     //     ^
     //     data
 
-    const char *buf = data;
+    buf = (const char*)data;
     while (size > 0) {
         size_t n = fwrite(buf, 1, size, f);
         if (ferror(f)) {
@@ -1406,7 +1413,7 @@ NOBDEF Nob_File_Type nob_get_file_type(const char *path)
     struct stat statbuf;
     if (lstat(path, &statbuf) < 0) {
         nob_log(NOB_ERROR, "Could not get stat of %s: %s", path, strerror(errno));
-        return -1;
+        return (Nob_File_Type)(-1);
     }
 
     if (S_ISREG(statbuf.st_mode)) return NOB_FILE_REGULAR;
@@ -1501,7 +1508,7 @@ NOBDEF bool nob_copy_directory_recursively(const char *src_path, const char *dst
 NOBDEF char *nob_temp_strdup(const char *cstr)
 {
     size_t n = strlen(cstr);
-    char *result = nob_temp_alloc(n + 1);
+    char *result = (char*)nob_temp_alloc(n + 1);
     NOB_ASSERT(result != NULL && "Increase NOB_TEMP_CAPACITY");
     memcpy(result, cstr, n);
     result[n] = '\0';
@@ -1526,7 +1533,7 @@ NOBDEF char *nob_temp_sprintf(const char *format, ...)
     va_end(args);
 
     NOB_ASSERT(n >= 0);
-    char *result = nob_temp_alloc(n + 1);
+    char *result = (char*)nob_temp_alloc(n + 1);
     NOB_ASSERT(result != NULL && "Extend the size of the temporary allocator");
     // TODO: use proper arenas for the temporary allocator;
     va_start(args, format);
@@ -1553,7 +1560,7 @@ NOBDEF void nob_temp_rewind(size_t checkpoint)
 
 NOBDEF const char *nob_temp_sv_to_cstr(Nob_String_View sv)
 {
-    char *result = nob_temp_alloc(sv.count + 1);
+    char *result = (char*)nob_temp_alloc(sv.count + 1);
     NOB_ASSERT(result != NULL && "Extend the size of the temporary allocator");
     memcpy(result, sv.data, sv.count);
     result[sv.count] = '\0';
@@ -1668,19 +1675,21 @@ NOBDEF bool nob_read_entire_file(const char *path, Nob_String_Builder *sb)
     bool result = true;
 
     FILE *f = fopen(path, "rb");
+    size_t new_count = 0;
+    long long m = 0;
     if (f == NULL)                 nob_return_defer(false);
     if (fseek(f, 0, SEEK_END) < 0) nob_return_defer(false);
 #ifndef _WIN32
-    long m = ftell(f);
+    m = ftell(f);
 #else
-    long long m = _ftelli64(f);
+    m = _ftelli64(f);
 #endif
     if (m < 0)                     nob_return_defer(false);
     if (fseek(f, 0, SEEK_SET) < 0) nob_return_defer(false);
 
-    size_t new_count = sb->count + m;
+    new_count = sb->count + m;
     if (new_count > sb->capacity) {
-        sb->items = NOB_REALLOC(sb->items, new_count);
+        sb->items = NOB_DECLTYPE_CAST(sb->items)NOB_REALLOC(sb->items, new_count);
         NOB_ASSERT(sb->items != NULL && "Buy more RAM lool!!");
         sb->capacity = new_count;
     }

shared.h

@@ -8,6 +8,8 @@
 #define BUILD_FOLDER "build/"
 #define TESTS_FOLDER "tests/"
 
+// TODO: we should test on C++ compilers too
+
 #if defined(_MSC_VER)
 #  define nob_cc_flags(cmd) cmd_append(cmd, "/W4", "/nologo", "/D_CRT_SECURE_NO_WARNINGS", "-I.")
 #elif defined(__APPLE__) || defined(__MACH__)

tests/cmd_redirect.c

@@ -9,6 +9,9 @@ int main(void)
     Cmd cmd = {0};
     Fd fdout = INVALID_FD;
     String_Builder sb = {0};
+    String_View actual_message = {0};
+    const char *message = NULL;
+    const char *message_file_path = NULL;
 
     const char *echo_src =
         "#include <assert.h>\n"
@@ -33,8 +36,8 @@ int main(void)
     nob_cc_inputs(&cmd, "./echo.c");
     if (!cmd_run(&cmd)) return_defer(1);
 
-    const char *message = "Hello, World";
-    const char *message_file_path = "./echo_message.txt";
+    message = "Hello, World";
+    message_file_path = "./echo_message.txt";
 
     fdout = fd_open_for_write(message_file_path);
     if (fdout == INVALID_FD) return_defer(1);
@@ -43,11 +46,11 @@ int main(void)
     if (!cmd_run(&cmd, .fdout = &fdout)) return_defer(1);
 
     if (!read_entire_file(message_file_path, &sb)) return_defer(1);
-    String_View actual_message = sb_to_sv(sb);
+    actual_message = sb_to_sv(sb);
     if (!sv_eq(sv_trim(actual_message), sv_from_cstr(message))) {
         nob_log(ERROR, "Unexpected message");
         nob_log(ERROR, "Expected: %s", message);
-        nob_log(ERROR, "Actual:   "SV_Fmt, SV_Arg(actual_message));
+        nob_log(ERROR, "Actual:   " SV_Fmt, SV_Arg(actual_message));
         return_defer(1);
     }