Add string formatting to Str8

src/core/strings/str8/str8.c

@@ -1,7 +1,9 @@
 #include "str8.h"
 #include "aliases.h"
 #include "mem_allocator.h"
+#include <stdarg.h>
 #include <stddef.h>
+#include <stdio.h>
 #include <string.h>
 #include <stdbool.h>
 
@@ -150,7 +152,7 @@ Str8 wapp_str8_slice(Str8RO *str, u64 start, u64 end) {
   };
 }
 
-Str8 *wapp_str8_concat(const Allocator *allocator, Str8 *dst, Str8RO *src) {
+Str8 *wapp_str8_alloc_concat(const Allocator *allocator, Str8 *dst, Str8RO *src) {
   if (!allocator || !dst || !src) {
     return NULL;
   }
@@ -226,6 +228,26 @@ void wapp_str8_copy_to_cstr(char *dst, Str8RO *src, u64 dst_capacity) {
   memcpy(dst, src->buf, to_copy);
 }
 
+void wapp_str8_format(Str8 *dst, const char *format, ...) {
+  if (!dst || !format) {
+    return;
+  }
+
+  va_list args1;
+  va_list args2;
+
+  va_start(args1, format);
+  va_copy(args2, args1);
+
+  u64 total_size = vsnprintf(NULL, 0, format, args1);
+  dst->size      = total_size <= dst->capacity ? total_size : dst->capacity;
+
+  vsnprintf((char *)(dst->buf), dst->capacity, format, args2);
+
+  va_end(args1);
+  va_end(args2);
+}
+
 i64 wapp_str8_find(Str8RO *str, Str8RO substr) {
   if (substr.size > str->size) {
     return -1;

src/core/strings/str8/str8.h

@@ -67,6 +67,7 @@ Str8 *wapp_str8_alloc_buf(const Allocator *allocator, u64 capacity);
 Str8 *wapp_str8_alloc_cstr(const Allocator *allocator, const char *str);
 Str8 *wapp_str8_alloc_str8(const Allocator *allocator, Str8RO *str);
 Str8 *wapp_str8_alloc_substr(const Allocator *allocator, Str8RO *str, u64 start, u64 end);
+Str8 *wapp_str8_alloc_concat(const Allocator *allocator, Str8 *dst, Str8RO *src);
 // Only needed for allocators like malloc where each allocation has to be freed on its own.
 // No need to use it for allocators like Arena.
 void wapp_str8_dealloc_buf(const Allocator *allocator, Str8 **str);
@@ -74,16 +75,16 @@ void wapp_str8_dealloc_buf(const Allocator *allocator, Str8 **str);
 /**
  * Str8 utilities
  */
-c8     wapp_str8_get(Str8RO *str, u64 index);
-void   wapp_str8_set(Str8 *str, u64 index, c8 c);
-bool   wapp_str8_equal(Str8RO *s1, Str8RO *s2);
-bool   wapp_str8_equal_to_count(Str8RO* s1, Str8RO* s2, u64 count);
-Str8   wapp_str8_slice(Str8RO *str, u64 start, u64 end);
-Str8   *wapp_str8_concat(const Allocator *allocator, Str8 *dst, Str8RO *src);
-void   wapp_str8_concat_capped(Str8 *dst, Str8RO *src);
-void   wapp_str8_copy_cstr_capped(Str8 *dst, const char *src);
-void   wapp_str8_copy_str8_capped(Str8 *dst, Str8RO *src);
-void   wapp_str8_copy_to_cstr(char *dst, Str8RO *src, u64 dst_capacity);
+c8   wapp_str8_get(Str8RO *str, u64 index);
+void wapp_str8_set(Str8 *str, u64 index, c8 c);
+bool wapp_str8_equal(Str8RO *s1, Str8RO *s2);
+bool wapp_str8_equal_to_count(Str8RO* s1, Str8RO* s2, u64 count);
+Str8 wapp_str8_slice(Str8RO *str, u64 start, u64 end);
+void wapp_str8_concat_capped(Str8 *dst, Str8RO *src);
+void wapp_str8_copy_cstr_capped(Str8 *dst, const char *src);
+void wapp_str8_copy_str8_capped(Str8 *dst, Str8RO *src);
+void wapp_str8_copy_to_cstr(char *dst, Str8RO *src, u64 dst_capacity);
+void wapp_str8_format(Str8 *dst, const char *format, ...);
 
 /**
  * Str8 find functions

src/os/shell/commander/commander.c

@@ -32,7 +32,7 @@ CMDResult wapp_shell_commander_execute(CMDOutHandling out_handling, Str8 *out_bu
   }
 
   // Redirect output
-  cmd_str = wapp_str8_concat(&arena, cmd_str, &wapp_str8_lit_ro(" 2>&1"));
+  cmd_str = wapp_str8_alloc_concat(&arena, cmd_str, &wapp_str8_lit_ro(" 2>&1"));
 
   CMDResult output = execute_command(cmd_str, out_handling, out_buf);