From 9be4ed5d89ecca80123311a4ec73781e5cc97a9c Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Fri, 27 Apr 2018 11:22:39 -0400 Subject: getopt_long_only: don't prefix-match long-options that match short ones for getopt_long, partial (prefix) matches of long options always begin with "--" and thus can never be ambiguous with a short option. for getopt_long_only, though, a single-character option can match both a short option and as a prefix for a long option. in this case, we wrongly interpreted it as a prefix for the long option. introduce a new pass, only in long-only mode, to check the prefix match against short options before accepting it. the only reason there's a slightly nontrivial loop being introduced rather than strchr is that our getopt already supports multibyte short options, and getopt_long_long should handle them consistently. a temp buffer and strstr could have been used, but the code to set it up would be just as large as what's introduced here and it would unnecessarily pull in relatively large code for strstr. --- src/misc/getopt_long.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/src/misc/getopt_long.c b/src/misc/getopt_long.c index 008b747c..ddcef949 100644 --- a/src/misc/getopt_long.c +++ b/src/misc/getopt_long.c @@ -1,5 +1,7 @@ #define _GNU_SOURCE #include +#include +#include #include #include #include @@ -58,10 +60,10 @@ static int __getopt_long_core(int argc, char *const *argv, const char *optstring { int colon = optstring[optstring[0]=='+'||optstring[0]=='-']==':'; int i, cnt, match; - char *arg, *opt; + char *arg, *opt, *start = argv[optind]+1; for (cnt=i=0; longopts[i].name; i++) { const char *name = longopts[i].name; - opt = argv[optind]+1; + opt = start; if (*opt == '-') opt++; while (*opt && *opt != '=' && *opt == *name) name++, opt++; @@ -74,6 +76,17 @@ static int __getopt_long_core(int argc, char *const *argv, const char *optstring } cnt++; } + if (cnt==1 && longonly && arg-start == mblen(start, MB_LEN_MAX)) { + int l = arg-start; + for (i=0; optstring[i]; i++) { + int j; + for (j=0; j