[hackers] [quark] Improve tokenization for m- and v-flag parsing || Laslo Hunhold

From: <git_AT_suckless.org>
Date: Sun, 24 Feb 2019 21:57:41 +0100 (CET)

commit 33def953e9d216036ad921ac26052a5b0fa790dc
Author: Laslo Hunhold <dev_AT_frign.de>
AuthorDate: Sun Feb 24 21:50:39 2019 +0100
Commit: Laslo Hunhold <dev_AT_frign.de>
CommitDate: Sun Feb 24 21:50:39 2019 +0100

    Improve tokenization for m- and v-flag parsing
    
    I wasn't happy with the tokenizer for the m- and v-flags, because it
    was handling space-separated input and there was no way to have spaces
    within the tokens themselves. This is a fine detail, but I didn't want
    to impose this restriction where it could be solved (path prefixes or
    folder names can very well contain spaces).
    
    Given it's a bit quirky to handle multiple arguments to a single flag
    in the command line, especially when parameters are optional, this
    alternative wasn't further considered and I instead implemented a
    tokenizer that allows escaping spaces with '\'.
    
    While at it, I clarified the manual regarding this point.
    
    Signed-off-by: Laslo Hunhold <dev_AT_frign.de>

diff --git a/main.c b/main.c
index 46cf424..9e7788f 100644
--- a/main.c
+++ b/main.c
_AT_@ -90,6 +90,77 @@ handlesignals(void(*hdl)(int))
         sigaction(SIGQUIT, &sa, NULL);
 }
 
+static int
+spacetok(const char *s, char **t, size_t tlen)
+{
+ const char *tok;
+ size_t i, j, toki, spaces;
+
+ /* fill token-array with NULL-pointers */
+ for (i = 0; i < tlen; i++) {
+ t[i] = NULL;
+ }
+ toki = 0;
+
+ /* don't allow NULL string or leading spaces */
+ if (!s || *s == ' ') {
+ return 1;
+ }
+start:
+ /* skip spaces */
+ for (; *s == ' '; s++)
+ ;
+
+ /* don't allow trailing spaces */
+ if (*s == '\0') {
+ goto err;
+ }
+
+ /* consume token */
+ for (tok = s, spaces = 0; ; s++) {
+ if (*s == '\\' && *(s + 1) == ' ') {
+ spaces++;
+ s++;
+ continue;
+ } else if (*s == ' ') {
+ /* end of token */
+ goto token;
+ } else if (*s == '\0') {
+ /* end of string */
+ goto token;
+ }
+ }
+token:
+ if (toki >= tlen) {
+ goto err;
+ }
+ if (!(t[toki] = malloc(s - tok - spaces + 1))) {
+ die("malloc:");
+ }
+ for (i = 0, j = 0; j < s - tok - spaces + 1; i++, j++) {
+ if (tok[i] == '\\' && tok[i + 1] == ' ') {
+ i++;
+ }
+ t[toki][j] = tok[i];
+ }
+ t[toki][s - tok - spaces] = '\0';
+ toki++;
+
+ if (*s == ' ') {
+ s++;
+ goto start;
+ }
+
+ return 0;
+err:
+ for (i = 0; i < tlen; i++) {
+ free(t[i]);
+ t[i] = NULL;
+ }
+
+ return 1;
+}
+
 static void
 usage(void)
 {
_AT_@ -113,7 +184,7 @@ main(int argc, char *argv[])
         socklen_t in_sa_len;
         int insock, status = 0, infd;
         const char *err;
- char *tok;
+ char *tok[4];
 
         /* defaults */
         int maxnprocs = 512;
_AT_@ -148,21 +219,16 @@ main(int argc, char *argv[])
                 s.listdirs = 1;
                 break;
         case 'm':
- if (!(tok = strdup(EARGF(usage())))) {
- die("strdup:");
+ if (spacetok(EARGF(usage()), tok, 3) || !tok[0] || !tok[1]) {
+ usage();
                 }
                 if (!(s.map = reallocarray(s.map, ++s.map_len,
                                            sizeof(struct map)))) {
                         die("reallocarray:");
                 }
- if (!(s.map[s.map_len - 1].from = strtok(tok, " ")) ||
- !(s.map[s.map_len - 1].to = strtok(NULL, " "))) {
- usage();
- }
- s.map[s.map_len - 1].chost = strtok(NULL, " ");
- if (strtok(NULL, "")) {
- usage();
- }
+ s.map[s.map_len - 1].from = tok[0];
+ s.map[s.map_len - 1].to = tok[1];
+ s.map[s.map_len - 1].chost = tok[2];
                 break;
         case 'n':
                 maxnprocs = strtonum(EARGF(usage()), 1, INT_MAX, &err);
_AT_@ -180,22 +246,18 @@ main(int argc, char *argv[])
                 user = EARGF(usage());
                 break;
         case 'v':
- if (!(tok = strdup(EARGF(usage())))) {
- die("strdup:");
+ if (spacetok(EARGF(usage()), tok, 4) || !tok[0] || !tok[1] ||
+ !tok[2]) {
+ usage();
                 }
                 if (!(s.vhost = reallocarray(s.vhost, ++s.vhost_len,
                                              sizeof(struct vhost)))) {
                         die("reallocarray:");
                 }
- if (!(s.vhost[s.vhost_len - 1].chost = strtok(tok, " ")) ||
- !(s.vhost[s.vhost_len - 1].regex = strtok(NULL, " ")) ||
- !(s.vhost[s.vhost_len - 1].dir = strtok(NULL, " "))) {
- usage();
- }
- s.vhost[s.vhost_len - 1].prefix = strtok(NULL, " ");
- if (strtok(NULL, "")) {
- usage();
- }
+ s.vhost[s.vhost_len - 1].chost = tok[0];
+ s.vhost[s.vhost_len - 1].regex = tok[1];
+ s.vhost[s.vhost_len - 1].dir = tok[2];
+ s.vhost[s.vhost_len - 1].prefix = tok[3];
                 break;
         default:
                 usage();
diff --git a/quark.1 b/quark.1
index 67d120a..ce315b5 100644
--- a/quark.1
+++ b/quark.1
_AT_@ -58,7 +58,8 @@ Add the target prefix mapping rule specified by
 .Ar map ,
 which has the form
 .Qq Pa from to [chost] ,
-where each element is separated with whitespace.
+where each element is separated with spaces (0x20) that can be
+escaped with '\\'.
 .Pp
 The prefix
 .Pa from
_AT_@ -96,7 +97,8 @@ Add the virtual host specified by
 .Ar vhost ,
 which has the form
 .Qq Pa chost regex dir [prefix] ,
-where each element is separated with whitespace.
+where each element is separated with spaces (0x20) that can be
+escaped with '\\'.
 .Pp
 A request matching the virtual host regular expression
 .Pa regex
Received on Sun Feb 24 2019 - 21:57:41 CET