refs.c::read_ref_at(): fix bogus munmap() call.

The code uses mmap() to read reflog data, but moves the pointer around
while reading, and uses that updated pointer in the call to munmap().

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/refs.c b/refs.c
index 87efa38c7e11fa05a320fb140dfcf5cb4e55da3c..6310cf46e0500cce2338f50b5bfeba622bce52d4 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1025,6 +1025,7 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
        struct stat st;
        unsigned long date;
        unsigned char logged_sha1[20];
+       void *log_mapped;
 
        logfile = git_path("logs/%s", ref);
        logfd = open(logfile, O_RDONLY, 0);
@@ -1033,7 +1034,8 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
        fstat(logfd, &st);
        if (!st.st_size)
                die("Log %s is empty.", logfile);
-       logdata = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
+       log_mapped = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd, 0);
+       logdata = log_mapped;
        close(logfd);
 
        lastrec = NULL;
@@ -1078,7 +1080,7 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
                                                logfile, show_rfc2822_date(date, tz));
                                }
                        }
-                       munmap((void*)logdata, st.st_size);
+                       munmap(log_mapped, st.st_size);
                        return 0;
                }
                lastrec = rec;
@@ -1095,7 +1097,7 @@ int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *
        tz = strtoul(tz_c, NULL, 10);
        if (get_sha1_hex(logdata, sha1))
                die("Log %s is corrupt.", logfile);
-       munmap((void*)logdata, st.st_size);
+       munmap(log_mapped, st.st_size);
        if (at_time)
                fprintf(stderr, "warning: Log %s only goes back to %s.\n",
                        logfile, show_rfc2822_date(date, tz));