remote-ext: do not segfault for blank lines

Instead of stripping space characters past the beginning of the
line and overflowing a buffer, stop at the beginning of the line
(mimicking the corresponding fix in remote-fd).

The argument to isspace does not need to be cast explicitly because
git isspace takes care of that already.

Noticed-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/remote-ext.c b/builtin/remote-ext.c
index 1f773171cbdde76cc105e37928cc5f2ecb2ed93f..ea71977c8360e1a7899bbd035cf26f93d889800b 100644 (file)
--- a/builtin/remote-ext.c
+++ b/builtin/remote-ext.c
@@ -212,16 +212,16 @@ static int command_loop(const char *child)
        char buffer[MAXCOMMAND];
 
        while (1) {
-               size_t length;
+               size_t i;
                if (!fgets(buffer, MAXCOMMAND - 1, stdin)) {
                        if (ferror(stdin))
                                die("Comammand input error");
                        exit(0);
                }
                /* Strip end of line characters. */
-               length = strlen(buffer);
-               while (isspace((unsigned char)buffer[length - 1]))
-                       buffer[--length] = 0;
+               i = strlen(buffer);
+               while (i > 0 && isspace(buffer[i - 1]))
+                       buffer[--i] = 0;
 
                if (!strcmp(buffer, "capabilities")) {
                        printf("*connect\n\n");