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-rw-r--r--contrib/ltree/crc32.c40
1 files changed, 40 insertions, 0 deletions
diff --git a/contrib/ltree/crc32.c b/contrib/ltree/crc32.c
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+++ b/contrib/ltree/crc32.c
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+/* contrib/ltree/crc32.c */
+
+/*
+ * Implements CRC-32, as used in ltree.
+ *
+ * Note that the CRC is used in the on-disk format of GiST indexes, so we
+ * must stay backwards-compatible!
+ */
+
+#include "postgres.h"
+#include "ltree.h"
+
+#ifdef LOWER_NODE
+#include <ctype.h>
+#define TOLOWER(x) tolower((unsigned char) (x))
+#else
+#define TOLOWER(x) (x)
+#endif
+
+#include "crc32.h"
+#include "utils/pg_crc.h"
+
+unsigned int
+ltree_crc32_sz(const char *buf, int size)
+{
+ pg_crc32 crc;
+ const char *p = buf;
+
+ INIT_TRADITIONAL_CRC32(crc);
+ while (size > 0)
+ {
+ char c = (char) TOLOWER(*p);
+
+ COMP_TRADITIONAL_CRC32(crc, &c, 1);
+ size--;
+ p++;
+ }
+ FIN_TRADITIONAL_CRC32(crc);
+ return (unsigned int) crc;
+}