prick_sv

prick_sv.h

@@ -0,0 +1,117 @@
+/* prick_sv.h: String Views.
+ * Created: 2026-03-01
+ * Author: Aryadev Chavali
+ * License: See end of file
+ * Commentary:
+
+ To utilise this library, please put:
+    #define PRICK_SV_IMPL
+    #include "prick_sv.h"
+ in one of your code units.
+
+ This is a simple read-only string view library.  It defines some extremely
+ common functions you'd expect for a string view library, excluding any that
+ require allocation.
+ */
+
+#ifndef PRICK_SV_H
+#define PRICK_SV_H
+
+#include <stdint.h>
+
+typedef struct
+{
+  uint64_t size;
+  const char *data;
+} prick_sv_t;
+
+#define PRICK_SV(DATA, SIZE) ((prick_sv_t){.data = (DATA), .size = (SIZE)})
+#define PRICK_SV_AUTO(DATA) \
+  ((prick_sv_t){.data = (void *)(DATA), .size = sizeof(DATA) - 1})
+
+// Pretty printers
+#define PRICK_SV_FMT(SV) (int)(SV).size, (SV).data
+#define PR_PRICK_SV      "%.*s"
+
+prick_sv_t prick_sv_chop_left(prick_sv_t, uint64_t size);
+prick_sv_t prick_sv_chop_right(prick_sv_t, uint64_t size);
+prick_sv_t prick_sv_truncate(prick_sv_t, uint64_t newsize);
+prick_sv_t prick_sv_substr(prick_sv_t, uint64_t position, uint64_t size);
+
+prick_sv_t prick_sv_till(prick_sv_t, const char *reject);
+prick_sv_t prick_sv_while(prick_sv_t, const char *accept);
+
+#ifdef PRICK_SV_IMPL
+#include <stddef.h>
+#include <string.h>
+
+prick_sv_t prick_sv_chop_left(prick_sv_t sv, uint64_t size)
+{
+  if (prick_sv.size <= size)
+    return PRICK_SV(NULL, 0);
+  return PRICK_SV(prick_sv.data + size, prick_sv.size - size);
+}
+
+prick_sv_t prick_sv_chop_right(prick_sv_t sv, uint64_t size)
+{
+  if (prick_sv.size <= size)
+    return PRICK_SV(NULL, 0);
+  return PRICK_SV(prick_sv.data, prick_sv.size - size);
+}
+
+prick_sv_t prick_sv_truncate(prick_sv_t sv, uint64_t newsize)
+{
+  if (newsize > prick_sv.size)
+    return PRICK_SV(NULL, 0);
+  return PRICK_SV(prick_sv.data, newsize);
+}
+
+prick_sv_t prick_sv_substr(prick_sv_t sv, uint64_t position, uint64_t size)
+{
+  prick_sv_t result = prick_sv_truncate(prick_sv_chop_left(sv, position), size);
+  return result;
+}
+
+prick_sv_t prick_sv_till(prick_sv_t sv, const char *reject)
+{
+  if (prick_sv.size == 0 || !prick_sv.data)
+    return PRICK_SV(NULL, 0);
+
+  uint64_t offset;
+  for (offset = 0;
+       offset < prick_sv.size && strchr(reject, prick_sv.data[offset]) == NULL;
+       ++offset)
+    continue;
+
+  return prick_sv_truncate(sv, offset);
+}
+
+prick_sv_t prick_sv_while(prick_sv_t sv, const char *accept)
+{
+  if (prick_sv.size == 0 || !prick_sv.data)
+    return PRICK_SV(NULL, 0);
+
+  uint64_t offset;
+  for (offset = 0;
+       offset < prick_sv.size && strchr(accept, prick_sv.data[offset]) != NULL;
+       ++offset)
+    continue;
+
+  return prick_sv_truncate(sv, offset);
+}
+
+#endif
+
+#endif
+
+/* Copyright (C) 2026 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 Unlicense for details.
+
+ * You may distribute and modify this code under the terms of the Unlicense,
+ * which you should have received a copy of along with this program.  If not,
+ * please go to <https://unlicense.org/>.
+
+ */