Cleanup option keyword/environment substitution
Right now the substitution for options seems quite fragile. Among the
issues...
- If bc had an error and returned no output, it caused a NULL reference
- Multiple variable substitutions (For example $ncpus * $pagesize)
caused an error as it tried to run bc after the first, with the second
still text
- Memory leak for every keyword substituted
- Multiplication caused shell wildcard expansion (*) of the current
directory when passing the input to bc
- Shell escape sequences would be parsed on the command line when bc is called
- Potential buffer overrun due to unchecked lengths on the input line
So I did a little cleanup to get rid of the issues. This patch also
moves the environment variable substitution to run before the keyword
substitution, so an environment variable can now indirectly perform a
keyword substitution.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/parse.c b/parse.c
index 18e8a40..7f7851c 100644
--- a/parse.c
+++ b/parse.c
@@ -199,9 +199,9 @@
if (len < 2)
return __get_mult_bytes(str, data, percent);
- /*
- * Go forward until we hit a non-digit, or +/- sign
- */
+ /*
+ * Go forward until we hit a non-digit, or +/- sign
+ */
while ((p - str) <= len) {
if (!isdigit((int) *p) &&
(((*p != '+') && (*p != '-')) || digit_seen))
@@ -798,83 +798,28 @@
return 1;
}
-/*
- * Return a copy of the input string with substrings of the form ${VARNAME}
- * substituted with the value of the environment variable VARNAME. The
- * substitution always occurs, even if VARNAME is empty or the corresponding
- * environment variable undefined.
- */
-static char *option_dup_subs(const char *opt)
-{
- char out[OPT_LEN_MAX+1];
- char in[OPT_LEN_MAX+1];
- char *outptr = out;
- char *inptr = in;
- char *ch1, *ch2, *env;
- ssize_t nchr = OPT_LEN_MAX;
- size_t envlen;
-
- if (strlen(opt) + 1 > OPT_LEN_MAX) {
- log_err("OPT_LEN_MAX (%d) is too small\n", OPT_LEN_MAX);
- return NULL;
- }
-
- in[OPT_LEN_MAX] = '\0';
- strncpy(in, opt, OPT_LEN_MAX);
-
- while (*inptr && nchr > 0) {
- if (inptr[0] == '$' && inptr[1] == '{') {
- ch2 = strchr(inptr, '}');
- if (ch2 && inptr+1 < ch2) {
- ch1 = inptr+2;
- inptr = ch2+1;
- *ch2 = '\0';
-
- env = getenv(ch1);
- if (env) {
- envlen = strlen(env);
- if (envlen <= nchr) {
- memcpy(outptr, env, envlen);
- outptr += envlen;
- nchr -= envlen;
- }
- }
-
- continue;
- }
- }
-
- *outptr++ = *inptr++;
- --nchr;
- }
-
- *outptr = '\0';
- return strdup(out);
-}
-
-int parse_option(const char *opt, struct fio_option *options, void *data)
+int parse_option(const char *opt, const char *input,
+ struct fio_option *options, void *data)
{
struct fio_option *o;
- char *post, *tmp;
+ char *post;
- tmp = option_dup_subs(opt);
- if (!tmp)
+ if (!opt) {
+ log_err("fio: failed parsing %s\n", input);
return 1;
+ }
- o = get_option(tmp, options, &post);
+ o = get_option(opt, options, &post);
if (!o) {
- log_err("Bad option <%s>\n", tmp);
- free(tmp);
+ log_err("Bad option <%s>\n", input);
return 1;
}
if (!handle_option(o, post, data)) {
- free(tmp);
return 0;
}
- log_err("fio: failed parsing %s\n", opt);
- free(tmp);
+ log_err("fio: failed parsing %s\n", input);
return 1;
}