merge-base --fork-point doc: clarify the example and failure modes

diff --git a/hex.c b/hex.c
index 899b74a08cb5298d2b0dd3205a98f5912a700e66..845b01a874b45314a22e6000bb4e7762c3dd846a 100644 (file)
--- a/hex.c
+++ b/hex.c
@@ -39,16 +39,8 @@ int get_sha1_hex(const char *hex, unsigned char *sha1)
 {
        int i;
        for (i = 0; i < GIT_SHA1_RAWSZ; i++) {
-               unsigned int val;
-               /*
-                * hex[1]=='\0' is caught when val is checked below,
-                * but if hex[0] is NUL we have to avoid reading
-                * past the end of the string:
-                */
-               if (!hex[0])
-                       return -1;
-               val = (hexval(hex[0]) << 4) | hexval(hex[1]);
-               if (val & ~0xff)
+               int val = hex2chr(hex);
+               if (val < 0)
                        return -1;
                *sha1++ = val;
                hex += 2;
@@ -61,12 +53,10 @@ int get_oid_hex(const char *hex, struct object_id *oid)
        return get_sha1_hex(hex, oid->hash);
 }
 
-char *sha1_to_hex(const unsigned char *sha1)
+char *sha1_to_hex_r(char *buffer, const unsigned char *sha1)
 {
-       static int bufno;
-       static char hexbuffer[4][GIT_SHA1_HEXSZ + 1];
        static const char hex[] = "0123456789abcdef";
-       char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
+       char *buf = buffer;
        int i;
 
        for (i = 0; i < GIT_SHA1_RAWSZ; i++) {
@@ -79,6 +69,19 @@ char *sha1_to_hex(const unsigned char *sha1)
        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];
+       bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
+       return sha1_to_hex_r(hexbuffer[bufno], sha1);
+}
+
 char *oid_to_hex(const struct object_id *oid)
 {
        return sha1_to_hex(oid->hash);