1 files changed, 94 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/bmhisrch.c b/reference/C/CONTRIB/SNIP/bmhisrch.c
new file mode 100755
index 0000000..13a6655
--- /dev/null
+++ b/reference/C/CONTRIB/SNIP/bmhisrch.c
@@ -0,0 +1,94 @@
+/*
+**  Case-Insensitive Boyer-Moore-Horspool pattern match
+**
+**  Public Domain version by Thad Smith 7/21/1992,
+**  based on a 7/92 public domain BMH version by Raymond Gardner.
+**
+**  This program is written in ANSI C and inherits the compilers
+**  ability (or lack thereof) to support non-"C" locales by use of
+**  toupper() and tolower() to perform case conversions.
+**  Limitation: pattern length + string length must be less than 32767.
+**
+**  10/21/93 rdg  Fixed bugs found by Jeff Dunlop
+*/
+
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+
+typedef unsigned char uchar;
+
+#define LARGE 32767             /* flag for last character match    */
+
+static int patlen;              /* # chars in pattern               */
+static int skip[UCHAR_MAX+1];   /* skip-ahead count for test chars  */
+static int skip2;               /* skip-ahead after non-match with
+                                ** matching final character         */
+static uchar *pat = NULL;       /* uppercase copy of pattern        */
+
+/*
+** bmhi_init() is called prior to bmhi_search() to calculate the
+** skip array for the given pattern.
+** Error: exit(1) is called if no memory is available.
+*/
+
+void bmhi_init(const char *pattern)
+{
+      int i, lastpatchar;
+      patlen = strlen(pattern);
+
+      /* Make uppercase copy of pattern */
+
+      pat = realloc ((void*)pat, patlen);
+      if (!pat)
+            exit(1);
+      for (i=0; i < patlen; i++)
+            pat[i] = toupper(pattern[i]);
+
+      /* initialize skip array */
+
+      for ( i = 0; i <= UCHAR_MAX; ++i )                    /* rdg 10/93 */
+            skip[i] = patlen;
+      for ( i = 0; i < patlen - 1; ++i )
+      {
+            skip[        pat[i] ] = patlen - i - 1;
+            skip[tolower(pat[i])] = patlen - i - 1;
+      }
+      lastpatchar = pat[patlen - 1];
+      skip[        lastpatchar ] = LARGE;
+      skip[tolower(lastpatchar)] = LARGE;
+      skip2 = patlen;                     /* Horspool's fixed second shift */
+      for (i = 0; i < patlen - 1; ++i)
+      {
+            if ( pat[i] == lastpatchar )
+                  skip2 = patlen - i - 1;
+      }
+}
+
+char *bmhi_search(const char *string, const int stringlen)
+{
+      int i, j;
+      char *s;
+
+      i = patlen - 1 - stringlen;
+      if (i >= 0)
+            return NULL;
+      string += stringlen;
+      for ( ;; )
+      {
+            while ( (i += skip[((uchar *)string)[i]]) < 0 )
+                  ;                           /* mighty fast inner loop */
+            if (i < (LARGE - stringlen))
+                  return NULL;
+            i -= LARGE;
+            j = patlen - 1;
+            s = (char *)string + (i - j);
+            while ( --j >= 0 && toupper(s[j]) == pat[j] )
+                  ;
+            if ( j < 0 )                                    /* rdg 10/93 */
+                  return s;                                 /* rdg 10/93 */
+            if ( (i += skip2) >= 0 )                        /* rdg 10/93 */
+                  return NULL;                              /* rdg 10/93 */
+      }
+}