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Revision 2ae38f2a65abae910ff7ad62861414d4333d01fc authored by Jeff King on 09 November 2016, 03:57:28 UTC, committed by Jeff King on 09 November 2016, 03:59:24 UTC 
sequencer: silence -Wtautological-constant-out-of-range-compare
 
When clang compiles sequencer.c, it complains:

  sequencer.c:632:14: warning: comparison of constant 2 with
    expression of type 'const enum todo_command' is always
    true [-Wtautological-constant-out-of-range-compare]
          if (command < ARRAY_SIZE(todo_command_strings))

This is because "command" is an enum that may only have two
values (0 and 1) and the array in question has two elements.

As it turns out, clang is actually wrong here, at least
according to its own bug tracker:

  https://llvm.org/bugs/show_bug.cgi?id=16154

But it's still worth working around this, as the warning is
present with -Wall, meaning we fail compilation with "make
DEVELOPER=1".

Casting the enum to size_t sufficiently unconfuses clang. As
a bonus, it also catches any possible out-of-bounds access
if the enum takes on a negative value (which shouldn't
happen either, but again, this is a defensive check).

Signed-off-by: Jeff King <peff@peff.net>
1 parent 791eb87
Raw File
hex.c 
#include "cache.h"

const signed char hexval_table[256] = {
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 00-07 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 08-0f */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 10-17 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 18-1f */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 20-27 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 28-2f */
	  0,  1,  2,  3,  4,  5,  6,  7,		/* 30-37 */
	  8,  9, -1, -1, -1, -1, -1, -1,		/* 38-3f */
	 -1, 10, 11, 12, 13, 14, 15, -1,		/* 40-47 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 48-4f */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 50-57 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 58-5f */
	 -1, 10, 11, 12, 13, 14, 15, -1,		/* 60-67 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 68-67 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 70-77 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 78-7f */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 80-87 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 88-8f */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 90-97 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* 98-9f */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* a0-a7 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* a8-af */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* b0-b7 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* b8-bf */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* c0-c7 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* c8-cf */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* d0-d7 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* d8-df */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* e0-e7 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* e8-ef */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* f0-f7 */
	 -1, -1, -1, -1, -1, -1, -1, -1,		/* f8-ff */
};

int get_sha1_hex(const char *hex, unsigned char *sha1)
{
	int i;
	for (i = 0; i < GIT_SHA1_RAWSZ; i++) {
		int val = hex2chr(hex);
		if (val < 0)
			return -1;
		*sha1++ = val;
		hex += 2;
	}
	return 0;
}

int get_oid_hex(const char *hex, struct object_id *oid)
{
	return get_sha1_hex(hex, oid->hash);
}

char *sha1_to_hex_r(char *buffer, const unsigned char *sha1)
{
	static const char hex[] = "0123456789abcdef";
	char *buf = buffer;
	int i;

	for (i = 0; i < GIT_SHA1_RAWSZ; i++) {
		unsigned int val = *sha1++;
		*buf++ = hex[val >> 4];
		*buf++ = hex[val & 0xf];
	}
	*buf = '\0';

	return buffer;
}

char *oid_to_hex_r(char *buffer, const struct object_id *oid)
{
	return sha1_to_hex_r(buffer, oid->hash);
}

char *sha1_to_hex(const unsigned char *sha1)
{
	static int bufno;
	static char hexbuffer[4][GIT_SHA1_HEXSZ + 1];
	return sha1_to_hex_r(hexbuffer[3 & ++bufno], sha1);
}

char *oid_to_hex(const struct object_id *oid)
{
	return sha1_to_hex(oid->hash);
}
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