Fixed `quad integer' (aka `long long') handling in ap_snprintf.c
More details were described in my original posting two weeks ago: ----------------------------------------------------------------------- Today (on my birthday ;) I've hacked on and cleaned up snprintf implementations for a forthcoming string library and discovered the following bug in ap_snprintf. If one tries to print a "long long" value which is just a little bit lower than the maximimum "unsigned long" (not "unsigned long long"!) value, ap_snprintf treats the value as a (signed) "long" instead of a "long long": | $ cat test.c | #include <stdio.h> | #include "ap_config.h" | #include "ap.h" | | int main(int argc, char *argv[]) | { | char buf[1024]; | | ap_snprintf(buf, sizeof(buf), "%qd %qd", 4294967290ULL, 4294967297ULL); | printf("ap_snprintf: \"%s\"\n", buf); | | sprintf(buf, "%qd %qd", 4294967290ULL, 4294967297ULL); | printf("sprintf: \"%s\"\n", buf); | } | $ cc -I../os/unix -I../include -o test test.c libap.a && ./test | ap_snprintf: "-6 4294967297" | sprintf: "4294967290 4294967297" The reason is a wrong optimization test in ap_snprintf.c which can be fixed this way: Index: ap_snprintf.c =================================================================== RCS file: /e/apache/REPOS/apache-1.3/src/ap/ap_snprintf.c,v retrieving revision 1.37 diff -u -r1.37 ap_snprintf.c --- ap_snprintf.c 1999/10/21 20:44:10 1.37 +++ ap_snprintf.c 1999/11/17 12:22:11 @@ -414,7 +413,7 @@ * If the value is less than the maximum unsigned long value, * then we know we aren't using quads, so use the faster function */ - if (num <= ULONG_MAX) + if (num <= ULONG_MAX && is_unsigned) return(conv_10( (wide_int)num, is_unsigned, is_negative, buf_end, len)); With this patch ap_snprintf and the (FreeBSD) vendor sprintf print the same values: | $ cc -I../os/unix -I../include -o test test.c libap.a && ./test | ap_snprintf: "4294967290 4294967297" | sprintf: "4294967290 4294967297" I think the patch is correct, although I have to admit that because of time I've not checked the whole quad-fiddling in ap_snprintf.c now. So I do not commit this myself. Instead someone else should review this first. ----------------------------------------------------------------------- git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@84179 13f79535-47bb-0310-9956-ffa450edef68
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