Fix a warning when using glibc's strcspn with clang.

With glibc 2.15 and clang 3.0, I get warnings from where we use the
strcpsn implementation in the header as strcspn(string, "=").  This
is apparently because clang sees that part of the strcspn macro
expands to "="[2], and doesn't realize that that part of the macro
is only evaluated when "="[1] != 0.
This commit is contained in:
Nick Mathewson 2012-06-26 10:55:23 -04:00
parent 9c8ec0aa20
commit 5fad3dc36b
2 changed files with 19 additions and 3 deletions

3
changes/clang_strcspn Normal file
View File

@ -0,0 +1,3 @@
o Minor bugfixes:
- Avoid a warning caused by using strcspn from glibc with clang 3.0.
Bugfix on 0.2.3.13-alpha.

View File

@ -3887,13 +3887,26 @@ tor_get_exit_code(const process_handle_t *process_handle,
return PROCESS_EXIT_EXITED; return PROCESS_EXIT_EXITED;
} }
/** Helper: return the number of characters in <b>s</b> preceding the first
* occurence of <b>ch</b>. If <b>ch</b> does not occur in <b>s</b>, return
* the length of <b>s</b>. Should be equivalent to strspn(s, "ch"). */
static INLINE size_t
str_num_before(const char *s, char ch)
{
const char *cp = strchr(s, ch);
if (cp)
return cp - s;
else
return strlen(s);
}
/** Return non-zero iff getenv would consider <b>s1</b> and <b>s2</b> /** Return non-zero iff getenv would consider <b>s1</b> and <b>s2</b>
* to have the same name as strings in a process's environment. */ * to have the same name as strings in a process's environment. */
int int
environment_variable_names_equal(const char *s1, const char *s2) environment_variable_names_equal(const char *s1, const char *s2)
{ {
size_t s1_name_len = strcspn(s1, "="); size_t s1_name_len = str_num_before(s1, '=');
size_t s2_name_len = strcspn(s2, "="); size_t s2_name_len = str_num_before(s2, '=');
return (s1_name_len == s2_name_len && return (s1_name_len == s2_name_len &&
tor_memeq(s1, s2, s1_name_len)); tor_memeq(s1, s2, s1_name_len));
@ -3968,7 +3981,7 @@ process_environment_make(struct smartlist_t *env_vars)
for (i = 0; i < n_env_vars; ++i) { for (i = 0; i < n_env_vars; ++i) {
const char *s = smartlist_get(env_vars_sorted, i); const char *s = smartlist_get(env_vars_sorted, i);
size_t slen = strlen(s); size_t slen = strlen(s);
size_t s_name_len = strcspn(s, "="); size_t s_name_len = str_num_before(s, '=');
if (s_name_len == slen) { if (s_name_len == slen) {
log_warn(LD_GENERAL, log_warn(LD_GENERAL,