Improve spawn program command parsing.

Closes #15

diff --git a/spectrwm.c b/spectrwm.c
index 00972db..34a49be 100644 (file)
--- a/spectrwm.c
+++ b/spectrwm.c
@@ -870,6 +870,7 @@ RB_HEAD(key_tree, key);
 
 /* function prototypes */
 void    adjust_font(struct ws_win *);
+char   *argsep(char **);
 void    bar_cleanup(struct swm_region *);
 void    bar_extra_setup(void);
 void    bar_extra_stop(void);
@@ -6255,24 +6256,73 @@ spawn_select(struct swm_region *r, union arg *args, const char *spawn_name,
        free(real_args);
 }
 
+/* Argument tokenizer. */
+char *
+argsep(char **sp) {
+       int                     single_quoted = 0, double_quoted = 0;
+       char                    *arg, *cp, *next;
+
+       if (*sp == NULL)
+               return NULL;
+
+       /* Eat and move characters until end of argument is found. */
+       for (arg = next = cp = *sp; *cp != '\0'; ++cp) {
+               if (!double_quoted && *cp == '\'') {
+                       /* Eat single-quote. */
+                       single_quoted = !single_quoted;
+               } else if (!single_quoted && *cp == '"') {
+                       /* Eat double-quote. */
+                       double_quoted = !double_quoted;
+               } else if (!single_quoted && *cp == '\\' && *(cp + 1) == '"') {
+                       /* Eat backslash; copy escaped character to arg. */
+                       *next++ = *(++cp);
+               } else if (!single_quoted && !double_quoted && *cp == '\\' &&
+                   (*(cp + 1) == '\'' || *(cp + 1) == ' ')) {
+                       /* Eat backslash; move escaped character. */
+                       *next++ = *(++cp);
+               } else if (!single_quoted && !double_quoted &&
+                   (*cp == ' ' || *cp == '\t')) {
+                       /* Terminate argument. */
+                       *next++ = '\0';
+                       /* Point sp to beginning of next argument. */
+                       *sp = ++cp;
+                       break;
+               } else {
+                       /* Move regular character. */
+                       *next++ = *cp;
+               }
+       }
+
+       /* Terminate argument if end of string. */
+       if (*cp == '\0') {
+               *next = '\0';
+               *sp = NULL;
+       }
+
+       return arg;
+}
+
 void
 spawn_insert(const char *name, const char *args, int flags)
 {
-       char                    *arg, *cp, *ptr;
        struct spawn_prog       *sp;
+       char                    *arg, *dup, *ptr;
+
+       DNPRINTF(SWM_D_SPAWN, "spawn_insert: %s[%s]\n", name, args);
 
-       DNPRINTF(SWM_D_SPAWN, "spawn_insert: %s\n", name);
+       if (args == NULL || *args == '\0')
+               return;
 
        if ((sp = calloc(1, sizeof *sp)) == NULL)
                err(1, "spawn_insert: calloc");
        if ((sp->name = strdup(name)) == NULL)
                err(1, "spawn_insert: strdup");
 
-       /* convert the arguments to an argument list */
-       if ((ptr = cp = strdup(args)) == NULL)
+       /* Convert the arguments to an argument list. */
+       if ((ptr = dup = strdup(args)) == NULL)
                err(1, "spawn_insert: strdup");
-       while ((arg = strsep(&ptr, " \t")) != NULL) {
-               /* empty field; skip it */
+       while ((arg = argsep(&ptr)) != NULL) {
+               /* Null argument; skip it. */
                if (*arg == '\0')
                        continue;
 
@@ -6283,10 +6333,11 @@ spawn_insert(const char *name, const char *args, int flags)
                if ((sp->argv[sp->argc - 1] = strdup(arg)) == NULL)
                        err(1, "spawn_insert: strdup");
        }
-       free(cp);
+       free(dup);
 
        sp->flags = flags;
 
+       DNPRINTF(SWM_D_SPAWN, "arg %d: [%s]\n", sp->argc, sp->argv[sp->argc-1]);
        TAILQ_INSERT_TAIL(&spawns, sp, entry);
        DNPRINTF(SWM_D_SPAWN, "spawn_insert: leave\n");
 }