[hackers] [sbase] comm: Print first trailing unpaired line in file 1 || Wolfgang Corcoran-Mathe

From: <git_AT_suckless.org>
Date: Tue, 4 Aug 2015 13:35:48 +0200 (CEST)

commit ac62259d242d7e54a2006140e863e9851fedcccb
Author: Wolfgang Corcoran-Mathe <first.lord.of.teal_AT_gmail.com>
AuthorDate: Mon Aug 3 15:30:35 2015 -0400
Commit: sin <sin_AT_2f30.org>
CommitDate: Tue Aug 4 12:35:44 2015 +0100

    comm: Print first trailing unpaired line in file 1
    
    Previously, a line read from file 1 before a strcmp was
    performed would be overwritten and lost. Something like
    this:
    
        comm one_line_file empty_file
    
    produced no output.
    
    This patch is a bit inelegant, but quite simple.

diff --git a/comm.c b/comm.c
index e0ec7b7..138b5ea 100644
--- a/comm.c
+++ b/comm.c
_AT_@ -33,7 +33,7 @@ main(int argc, char *argv[])
 {
         FILE *fp[2];
         size_t linelen[2] = { 0, 0 };
- int ret = 0, i, diff = 0;
+ int ret = 0, i, diff = 0, seenline = 0;
         char *line[2] = { NULL, NULL };
 
         ARGBEGIN {
_AT_@ -62,11 +62,13 @@ main(int argc, char *argv[])
                 for (i = 0; i < 2; i++) {
                         if (diff && i == (diff < 0))
                                 continue;
- if (getline(&line[i], &linelen[i], fp[i]) > 0)
+ if (getline(&line[i], &linelen[i], fp[i]) > 0) {
+ seenline = 1;
                                 continue;
+ }
                         if (ferror(fp[i]))
                                 eprintf("getline %s:", argv[i]);
- if (diff && line[!i][0])
+ if ((diff || seenline) && line[!i][0])
                                 printline(!i, line[!i]);
                         while (getline(&line[!i], &linelen[!i], fp[!i]) > 0)
                                 printline(!i, line[!i]);
_AT_@ -76,6 +78,7 @@ main(int argc, char *argv[])
                 }
                 diff = strcmp(line[0], line[1]);
                 LIMIT(diff, -1, 1);
+ seenline = 0;
                 printline((2 - diff) % 3, line[MAX(0, diff)]);
         }
 end:
Received on Tue Aug 04 2015 - 13:35:48 CEST