Initial implementation

sv.c

@@ -0,0 +1,158 @@
+/* Copyright (C) 2025 Aryadev Chavali
+
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License Version 2 for
+ * details.
+
+ * You may distribute and modify this code under the terms of the GNU General
+ * Public License Version 2, which you should have received a copy of along with
+ * this program.  If not, please go to <https://www.gnu.org/licenses/>.
+
+ * Created: 2025-04-14
+ * Description: String View implementation
+ */
+
+#include "./sv.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+sv_t sv_make(arena_t *allocator, const char *data, u64 size)
+{
+  sv_t s = {0};
+  if (data)
+    s = sv_append(allocator, s, data, size);
+  else
+  {
+    s.data = arena_alloc(allocator, size);
+    s.size = size;
+  }
+  return s;
+}
+
+sv_t sv_copy(arena_t *allocator, sv_t sv)
+{
+  return sv_make(allocator, sv.data, sv.size);
+}
+
+sv_t sv_substr(sv_t sv, u64 index, u64 size)
+{
+  sv_t newsv = {0};
+  if (index + size > sv.size)
+    return newsv;
+  newsv.data = sv.data + index;
+  newsv.size = size;
+  return newsv;
+}
+
+sv_t sv_cut(sv_t sv, u64 index)
+{
+  return sv_substr(sv, index, sv.size < index ? 0 : sv.size - index);
+}
+
+sv_t sv_chop(sv_t sv, u64 size)
+{
+  return sv_substr(sv, 0, size);
+}
+
+sv_t sv_concat(arena_t *allocator, sv_t a, sv_t b)
+{
+  sv_t c = sv_make(allocator, a.data, a.size + b.size);
+  memcpy(c.data + a.size, b.data, b.size);
+  return c;
+}
+
+sv_t sv_append(arena_t *allocator, sv_t sv, const char *data, u64 size)
+{
+  if (!allocator)
+    return (sv_t){0};
+
+  sv_t newsv = {0};
+  newsv.size = sv.size + size;
+  newsv.data = arena_realloc(allocator, sv.data, sv.size, newsv.size);
+  if (data)
+    memcpy(newsv.data + sv.size, data, size);
+  return newsv;
+}
+
+sv_t sv_prepend(arena_t *allocator, sv_t sv, const char *data, u64 size)
+{
+  if (!allocator)
+    return (sv_t){0};
+
+  // TODO: Can we make this cheaper to do?
+  sv_t newsv = sv_make(allocator, NULL, size + sv.size);
+  // Copy over `data` to the left side
+  memcpy(newsv.data, data, size);
+  // Copy old string to the right side
+  if (sv.data)
+    memcpy(newsv.data + size, sv.data, sv.size);
+
+  return newsv;
+}
+
+sv_t sv_fmt(arena_t *allocator, char *fmt, ...)
+{
+  if (!allocator)
+    return (sv_t){0};
+
+  va_list ap_1, ap_2;
+  va_start(ap_1, fmt);
+
+  va_copy(ap_2, ap_1);
+  u64 size = vsnprintf(NULL, 0, fmt, ap_2);
+  va_end(ap_2);
+
+  sv_t sv = sv_make(allocator, NULL, size);
+  vsprintf(sv.data, fmt, ap_1);
+  va_end(ap_1);
+
+  return sv;
+}
+
+i64 sv_find_substr(const sv_t sv, const sv_t substr)
+{
+  if (substr.size == 0)
+    return 0;
+  else if (sv.size < substr.size)
+    return -1;
+  else if (sv.size == substr.size)
+    return strncmp(sv.data, substr.data, sv.size) == 0 ? 0 : -1;
+
+  for (u64 i = 0; i < (sv.size - substr.size); ++i)
+    if (strncmp(sv.data + i, substr.data, substr.size) == 0)
+      return i;
+  return -1;
+}
+
+i64 sv_find_subcstr(const sv_t sv, const char *substr, u64 size)
+{
+  return sv_find_substr(sv, SV((char *)substr, size));
+}
+
+i64 sv_find_any(const sv_t sv, const char *bag)
+{
+  for (u64 i = 0; i < sv.size; ++i)
+    if (strchr(bag, sv.data[i]))
+      return i;
+  return -1;
+}
+
+u64 sv_while(const sv_t sv, bool (*pred)(char))
+{
+  u64 i;
+  for (i = 0; i < sv.size && pred(sv.data[i]); ++i)
+    continue;
+  return i;
+}
+
+u64 sv_till(const sv_t sv, bool (*pred)(char))
+{
+  u64 i;
+  for (i = 0; i < sv.size && !pred(sv.data[i]); ++i)
+    continue;
+  return i;
+}