aboutsummaryrefslogtreecommitdiff
path: root/time/tzfile.c
diff options
context:
space:
mode:
Diffstat (limited to 'time/tzfile.c')
-rw-r--r--time/tzfile.c42
1 files changed, 33 insertions, 9 deletions
diff --git a/time/tzfile.c b/time/tzfile.c
index d80789d570..761ddc9539 100644
--- a/time/tzfile.c
+++ b/time/tzfile.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991, 92, 93, 95, 96 Free Software Foundation, Inc.
+/* Copyright (C) 1991, 92, 93, 95, 96, 97 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -113,16 +113,28 @@ __tzfile_read (const char *file)
if (*file != '/')
{
- static const char tzdir[] = TZDIR;
- register const unsigned int len = strlen (file) + 1;
- char *new = (char *) __alloca (sizeof (tzdir) + len);
- memcpy (new, tzdir, sizeof(tzdir) - 1);
- new[sizeof (tzdir) - 1] = '/';
- memcpy (&new[sizeof (tzdir)], file, len);
+ static const char default_tzdir[] = TZDIR;
+ const char *tzdir;
+ unsigned int len, tzdir_len;
+ char *new;
+
+ tzdir = __secure_getenv ("TZDIR");
+ if (tzdir == NULL || *tzdir == '\0')
+ {
+ tzdir = default_tzdir;
+ tzdir_len = sizeof (default_tzdir) - 1;
+ }
+ else
+ tzdir_len = strlen (tzdir);
+ len = strlen (file) + 1;
+ new = (char *) __alloca (tzdir_len + 1 + len);
+ memcpy (new, tzdir, tzdir_len);
+ new[tzdir_len] = '/';
+ memcpy (&new[tzdir_len + 1], file, len);
file = new;
}
- f = fopen(file, "r");
+ f = fopen (file, "r");
if (f == NULL)
return;
@@ -171,6 +183,12 @@ __tzfile_read (const char *file)
fread(type_idxs, 1, num_transitions, f) != num_transitions)
goto lose;
+ /* Check for bogus indices in the data file, so we can hereafter
+ safely use type_idxs[T] as indices into `types' and never crash. */
+ for (i = 0; i < num_transitions; ++i)
+ if (type_idxs[i] >= num_types)
+ goto lose;
+
if (BYTE_ORDER != BIG_ENDIAN || sizeof (time_t) != 4)
{
/* Decode the transition times, stored as 4-byte integers in
@@ -189,6 +207,8 @@ __tzfile_read (const char *file)
fread (&types[i].isdst, 1, 1, f) != 1 ||
fread (&types[i].idx, 1, 1, f) != 1)
goto lose;
+ if (types[i].idx >= chars) /* Bogus index in data file. */
+ goto lose;
types[i].offset = (long int) decode (x);
}
@@ -335,6 +355,10 @@ __tzfile_default (char *std, char *dst, long int stdoff, long int dstoff)
types[1].offset = dstoff;
types[1].isdst = 1;
+ /* Reset the zone names to point to the user's names. */
+ __tzname[0] = &zone_names[0];
+ __tzname[1] = &zone_names[stdlen];
+
compute_tzname_max (stdlen + dstlen);
}
@@ -425,7 +449,7 @@ compute_tzname_max (size_t chars)
const char *start = p;
while (*p != '\0')
++p;
- if (p - start > __tzname_cur_max)
+ if ((size_t) (p - start) > __tzname_cur_max)
__tzname_cur_max = p - start;
} while (++p < &zone_names[chars]);
}