allow arguments in hook Exec fields

Signed-off-by: Andrew Gregory <andrew.gregory.8@gmail.com>
Signed-off-by: Allan McRae <allan@archlinux.org>

1 files changed, 124 insertions, 5 deletions

diff --git a/lib/libalpm/hook.c b/lib/libalpm/hook.c
index 0191a21e..bff072d6 100644
--- a/lib/libalpm/hook.c
+++ b/lib/libalpm/hook.c
@@ -17,6 +17,7 @@
  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <ctype.h>
 #include <dirent.h>
 #include <errno.h>
 #include <string.h>
@@ -49,7 +50,7 @@ struct _alpm_hook_t {
 	char *name;
 	alpm_list_t *triggers;
 	alpm_list_t *depends;
-	char *cmd;
+	char **cmd;
 	enum _alpm_hook_when_t when;
 	int abort_on_fail;
 };
@@ -67,11 +68,22 @@ static void _alpm_trigger_free(struct _alpm_trigger_t *trigger)
 	}
 }
 
+static void _alpm_wordsplit_free(char **ws)
+{
+	if(ws) {
+		char **c;
+		for(c = ws; *c; c++) {
+			free(*c);
+		}
+		free(ws);
+	}
+}
+
 static void _alpm_hook_free(struct _alpm_hook_t *hook)
 {
 	if(hook) {
 		free(hook->name);
-		free(hook->cmd);
+		_alpm_wordsplit_free(hook->cmd);
 		alpm_list_free_inner(hook->triggers, (alpm_list_fn_free) _alpm_trigger_free);
 		alpm_list_free(hook->triggers);
 		FREELIST(hook->depends);
@@ -141,6 +153,107 @@ static int _alpm_hook_validate(alpm_handle_t *handle,
 	return ret;
 }
 
+static char **_alpm_wordsplit(char *str)
+{
+	char *c = str, *end;
+	char **out = NULL, **outsave;
+	size_t count = 0;
+
+	if(str == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	for(c = str; isspace(*c); c++);
+	while(*c) {
+		size_t wordlen = 0;
+
+		/* extend our array */
+		outsave = out;
+		if((out = realloc(out, (count + 1) * sizeof(char*))) == NULL) {
+			out = outsave;
+			goto error;
+		}
+
+		/* calculate word length and check for unbalanced quotes */
+		for(end = c; *end && !isspace(*end); end++) {
+			if(*end == '\'' || *end == '"') {
+				char quote = *end;
+				while(*(++end) && *end != quote) {
+					if(*end == '\\' && *(end + 1) == quote) {
+						end++;
+					}
+					wordlen++;
+				}
+				if(*end != quote) {
+					errno = EINVAL;
+					goto error;
+				}
+			} else {
+				if(*end == '\\' && (end[1] == '\'' || end[1] == '"')) {
+					end++; /* skip the '\\' */
+				}
+				wordlen++;
+			}
+		}
+
+		if(wordlen == (size_t) (end - c)) {
+			/* no internal quotes or escapes, copy it the easy way */
+			if((out[count++] = strndup(c, wordlen)) == NULL) {
+				goto error;
+			}
+		} else {
+			/* manually copy to remove quotes and escapes */
+			char *dest = out[count++] = malloc(wordlen + 1);
+			if(dest == NULL) { goto error; }
+			while(c < end) {
+				if(*c == '\'' || *c == '"') {
+					char quote = *c;
+					/* we know there must be a matching end quote,
+					 * no need to check for '\0' */
+					for(c++; *c != quote; c++) {
+						if(*c == '\\' && *(c + 1) == quote) {
+							c++;
+						}
+						*(dest++) = *c;
+					}
+					c++;
+				} else {
+					if(*c == '\\' && (c[1] == '\'' || c[1] == '"')) {
+						c++; /* skip the '\\' */
+					}
+					*(dest++) = *(c++);
+				}
+			}
+			*dest = '\0';
+		}
+
+		if(*end == '\0') {
+			break;
+		} else {
+			for(c = end + 1; isspace(*c); c++);
+		}
+	}
+
+	outsave = out;
+	if((out = realloc(out, (count + 1) * sizeof(char*))) == NULL) {
+		out = outsave;
+		goto error;
+	}
+
+	out[count++] = NULL;
+
+	return out;
+
+error:
+	/* can't use wordsplit_free here because NULL has not been appended */
+	while(count) {
+		free(out[--count]);
+	}
+	free(out);
+	return NULL;
+}
+
 static int _alpm_hook_parse_cb(const char *file, int line,
 		const char *section, char *key, char *value, void *data)
 {
@@ -208,7 +321,14 @@ static int _alpm_hook_parse_cb(const char *file, int line,
 		} else if(strcmp(key, "AbortOnFail") == 0) {
 			hook->abort_on_fail = 1;
 		} else if(strcmp(key, "Exec") == 0) {
-			STRDUP(hook->cmd, value, return 1);
+			if((hook->cmd = _alpm_wordsplit(value)) == NULL) {
+				if(errno == EINVAL) {
+					error(_("hook %s line %d: invalid value %s\n"), file, line, value);
+				} else {
+					error(_("hook %s line %d: unable to set option (%s)\n"),
+							file, line, strerror(errno));
+				}
+			}
 		} else {
 			error(_("hook %s line %d: invalid option %s\n"), file, line, key);
 		}
@@ -383,7 +503,6 @@ static alpm_list_t *find_hook(alpm_list_t *haystack, const void *needle)
 static int _alpm_hook_run_hook(alpm_handle_t *handle, struct _alpm_hook_t *hook)
 {
 	alpm_list_t *i, *pkgs = _alpm_db_get_pkgcache(handle->db_local);
-	char *const argv[] = { hook->cmd, NULL };
 
 	for(i = hook->depends; i; i = i->next) {
 		if(!alpm_find_satisfier(pkgs, i->data)) {
@@ -393,7 +512,7 @@ static int _alpm_hook_run_hook(alpm_handle_t *handle, struct _alpm_hook_t *hook)
 		}
 	}
 
-	return _alpm_run_chroot(handle, hook->cmd, argv);
+	return _alpm_run_chroot(handle, hook->cmd[0], hook->cmd);
 }
 
 int _alpm_hook_run(alpm_handle_t *handle, enum _alpm_hook_when_t when)