On Sun, Apr 06, 2008 at 02:03:45PM +0100, James Youngman wrote:
> login-utils/Makefile.am | 7 ++-
> login-utils/islocal.c | 164 +++++++++++++++++++++++++++++++++++++++++-----
> login-utils/islocal.h | 2 +-
> 3 files changed, 153 insertions(+), 20 deletions(-)
Hmm...
> int
> -is_local(char *user)
> +is_local(const char *user)
> {
> - FILE *fd;
> - char line[MAX_LENGTH];
> int local = 0;
> - size_t len;
> -
> - if(!(fd = fopen(_PATH_PASSWD, "r"))) {
> - fprintf(stderr,_("Can't read %s, exiting."),_PATH_PASSWD);
> - exit(1);
> - }
> + size_t match;
> + int chin, skip;
> + FILE *f = fopen_passwd_file();
>
> - len = strlen(user);
> - while(fgets(line, MAX_LENGTH, fd)) {
> - if(!strncmp(line, user, len) && line[len] == ':') {
> - local = 1;
> - break;
> - }
> + match = 0u;
> + skip = 0;
> + while ((chin=getc(f)) != EOF) {
> + if (skip) {
> + /* Looking for the start of the next line. */
> + if ('\n' == chin) {
> + /* Start matching username at the next char. */
> + skip = 0;
> + match = 0u;
> + }
> + } else {
> + if (':' == chin) {
> + if (0 == user[match]) {
> + local = 1; /* Success. */
> + /* next line has no test coverage, but it is
> + * just an optimisation anyway. */
> + break;
> + } else {
> + /* we read a whole username, but it is
> + * the wrong user. Skip to the next
> + * line. */
> + skip = 1;
> + }
> + } else if ('\n' == chin) {
> + /* This line contains no colon; it's malformed.
> + * No skip since we are already at the start of
> + * the next line. */
> + match = 0u;
> + } else if (chin != user[match]) {
> + /* username does not match. */
> + skip = 1;
> + } else {
> + ++match;
> + }
> + }
> }
> - fclose(fd);
> + fclose(f);
> return local;
> }
What about:
login-utils/islocal.c | 13 ++++++++-----
1 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/login-utils/islocal.c b/login-utils/islocal.c
index 2976980..7fa1434 100644
--- a/login-utils/islocal.c
+++ b/login-utils/islocal.c
@@ -24,13 +24,11 @@
#include "pathnames.h"
#include "islocal.h"
-#define MAX_LENGTH 1024
-
int
is_local(char *user)
{
FILE *fd;
- char line[MAX_LENGTH];
+ char *line;
int local = 0;
size_t len;
@@ -40,12 +38,17 @@ is_local(char *user)
}
len = strlen(user);
- while(fgets(line, MAX_LENGTH, fd)) {
- if(!strncmp(line, user, len) && line[len] == ':') {
+ line = malloc(len + 2); /* 2 = ":\0" */
+
+ while(fgets(line, len + 2, fd)) {
+ int c = line[len];
+ if(!strncmp(line, user, len) && c == ':') {
local = 1;
break;
}
+ while(c != '\n' && (c = fgetc(fd)) != EOF);
}
+ free(line);
fclose(fd);
return local;
}
It could be also easily reimplemented with fixed-length (LOGIN_NAME_MAX)
buffer and fscanf().
> +#if MAIN_TEST_ISLOCAL
> +static unsigned failures = 0u;
> +static const char *testdata =
> +"root:x:0:0:root:/root:/bin/bash\n"
> +"sys:x:3:3:sys:/dev:/bin/sh\n"
> +"orac:x:33:33:sys:/dev:/bin/youngman\n"
> +/* Next line should be >1024 but <2048 */
> +"long:x:4:4:foo:/home/loooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
> oooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooonnnggg:/bin/sh\n"
> +"al:x:5:5:fnord:/dev:/bin/sh\n"
> +"abcdefgh:x:6:3:fnord:/dev:/bin/sh\n"
> +"malformed\n"
> +"\n" /* see test case znobody */
> +"nobody:x:65534:65534:nobody:/nonexistent:/bin/sh\n"
> +"nonl:x:65532:65532:no newline:/:/bin/false";
I really don't like this kind of test. We have the test/ directory
where you can store all test data. Your MAIN_TEST_XXX needs to
include really necessary _code_ only.
Karel
--
Karel Zak <kzak@xxxxxxxxxx>
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