X-Git-Url: https://git.distorted.org.uk/~mdw/mLib/blobdiff_plain/18c831dcd0ae4d660c70ccac69d27ed2a97851be..3e7267bfb1faa4895769c785d859a88e86a79ff5:/hash/crc-mktab.c

diff --git a/hash/crc-mktab.c b/hash/crc-mktab.c
index d6f4149..4453cf3 100644
--- a/hash/crc-mktab.c
+++ b/hash/crc-mktab.c
@@ -57,6 +57,7 @@ static FILE *fp;
 #define f_bogus 1u
 #define f_ctab 2u
 #define f_reverse 4u
+#define f_const 8u
 
 #define BSCOL 72
 
@@ -79,7 +80,7 @@ static void version(FILE *fp)
 
 static void usage(FILE *fp)
 {
-  pquis(fp, "Usage: $ [-cr] [-o FILE] [-g GUARD] [-s SYM] [-i HEADER]\n\
+  pquis(fp, "Usage: $ [-Ccr] [-o FILE] [-g GUARD] [-s SYM] [-i HEADER]\n\
 	[-t TYPE] [-b BITS] [-B BITS] [-p POLY]\n");
 }
 
@@ -97,6 +98,7 @@ of options are provided:\n\
 -u, --usage		Show a terse usage message.\n\
 \n\
 -c, --c-source		Emit a C source file rather than a header.\n\
+-C, --const		Declare table to be `const' (only useful with `-c').\n\
 -b, --bits=BITS		Emit a table for a BITS bits-wide CRC.\n\
 -B, --bit-chunk=BITS	Emit a table to process BITS bits at a time.\n\
 -p, --polynomial=POLY	Use the POLY as the dividing polynomial.\n\
@@ -117,7 +119,7 @@ unsigned long reflect(unsigned long x, unsigned b)
   if (!(flags & f_reverse))
     return (x);
   xm = 1;
-  ym = 1 << (b - 1);
+  ym = 1u << (b - 1);
   for (i = 0; i < b; i++) {
     if (x & xm)
       y |= ym;
@@ -143,6 +145,7 @@ int main(int argc, char *argv[])
 
       { "output",	OPTF_ARGREQ,	0,	'o' },
       { "c-source",	0,		0,	'c' },
+      { "const",	0,		0,	'C' },
       { "symbol",	OPTF_ARGREQ,	0,	's' },
       { "type",		OPTF_ARGREQ,	0,	't' },
       { "include",	OPTF_ARGREQ,	0,	'i' },
@@ -155,7 +158,7 @@ int main(int argc, char *argv[])
 
       { 0,		0,		0,	0 }
     };
-    int i = mdwopt(argc, argv, "hvu o:cs:t:i:g: b:B:p:r", opts, 0, 0, 0);
+    int i = mdwopt(argc, argv, "hvu o:cCs:t:i:g: b:B:p:r", opts, 0, 0, 0);
 
     if (i < 0)
       break;
@@ -176,6 +179,9 @@ int main(int argc, char *argv[])
       case 'c':
 	flags |= f_ctab;
 	break;
+      case 'C':
+	flags |= f_const;
+	break;
       case 's':
 	sym = optarg;
 	break;
@@ -287,7 +293,8 @@ int main(int argc, char *argv[])
   if (flags & f_ctab) {
     if (inc)
       fprintf(fp, "#include \"%s\"\n\n", inc);
-    fprintf(fp, "%s %s[] = {\n", type, sym);
+    fprintf(fp, "%s%s %s[] = {\n",
+	    (flags&f_const) ? "const " : "", type, sym);
   } else {
     int n;
     if (guard)