Add functions to dynamically allocate strings

src/core/strings/str8/str8.c

@@ -1,7 +1,73 @@
 #include "str8.h"
 #include "aliases.h"
+#include "mem_allocator.h"
 #include <string.h>
 
+Str8 *wapp_str8_buf_alloc(const Allocator *allocator, u64 capacity) {
+  Str8 *str = NULL;
+
+  if (!allocator) {
+    goto RETURN_STR8;
+  }
+
+  str = wapp_mem_allocator_alloc(allocator, sizeof(Str8));
+  if (!str) {
+    goto RETURN_STR8;
+  }
+
+  c8 *buf = wapp_mem_allocator_alloc(allocator, sizeof(c8) * capacity);
+  if (!buf) {
+    wapp_mem_allocator_free(allocator, (void **)&str);
+    goto RETURN_STR8;
+  }
+
+  str->buf      = buf;
+  str->size     = 0;
+  str->capacity = capacity;
+
+RETURN_STR8:
+  return str;
+}
+
+Str8 *wapp_str8_alloc_cstr(const Allocator *allocator, const char *str) {
+  Str8 *output = NULL;
+
+  if (!allocator || !str) {
+    goto RETURN_ALLOC_CSTR;
+  }
+
+  u64 length = strlen(str);
+  output     = wapp_str8_buf_alloc(allocator, length * 2);
+  if (!output) {
+    goto RETURN_ALLOC_CSTR;
+  }
+
+  output->size = length;
+  memcpy(output->buf, str, length);
+
+RETURN_ALLOC_CSTR:
+  return output;
+}
+
+Str8 *wapp_str8_alloc_str8(const Allocator *allocator, Str8RO *str) {
+  Str8 *output = NULL;
+
+  if (!allocator || !str) {
+    goto RETURN_ALLOC_STR8;
+  }
+
+  output = wapp_str8_buf_alloc(allocator, str->capacity);
+  if (!output) {
+    goto RETURN_ALLOC_STR8;
+  }
+
+  output->size = str->size;
+  memcpy(output->buf, str->buf, str->size);
+
+RETURN_ALLOC_STR8:
+  return output;
+}
+
 c8 wapp_str8_get(const Str8 *str, u64 index) {
   if (index >= str->size) {
     return '\0';
@@ -18,6 +84,22 @@ void wapp_str8_set(Str8 *str, u64 index, c8 c) {
   str->buf[index] = c;
 }
 
+Str8RO wapp_str8_substr(Str8RO *str, u64 start, u64 end) {
+  if (start >= str->size || start >= end) {
+    return (Str8RO){0};
+  }
+
+  if (end > str->size) {
+    end = str->size;
+  }
+
+  return (Str8RO){
+    .capacity = end - start,
+    .size     = end - start,
+    .buf      = str->buf + start,
+  };
+}
+
 i64 wapp_str8_find(Str8RO *str, Str8RO substr) {
   if (substr.size > str->size) {
     return -1;

src/core/strings/str8/str8.h

@@ -2,6 +2,7 @@
 #define STR8_H
 
 #include "aliases.h"
+#include "mem_allocator.h"
 #include <string.h>
 
 #ifdef __cplusplus
@@ -32,8 +33,13 @@ typedef const Str8 Str8RO;
                                            .size     = sizeof(STRING) - 1, \
                                            .buf      = (c8 *)STRING})
 
+Str8 *wapp_str8_buf_alloc(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);
+
 c8     wapp_str8_get(Str8RO *str, u64 index);
 void   wapp_str8_set(Str8 *str, u64 index, c8 c);
+Str8RO wapp_str8_substr(Str8RO *str, u64 start, u64 end);
 
 i64 wapp_str8_find(Str8RO *str, Str8RO substr);
 i64 wapp_str8_rfind(Str8RO *str, Str8RO substr);