Add our own version of execve for GNO, which can quote arguments and can remove variables from the environment if needed.

Our versions of the execv* functions have been moved to their own file. They are now used for all the exec* calls in hush.

Makefile

@@ -36,7 +36,8 @@ LIBBB_B_SRC = \
 	libbb/messages.c \
 	libbb/bb.basename.c \
 	libbb/mempcpy.c \
-	libbb/get.exec.path.c
+	libbb/get.exec.path.c \
+	libbb/exec.gno.c
 
 LIBBB_C_SRC = \
 	libbb/perror.msg.c \

libbb/exec.gno.c

@@ -0,0 +1,91 @@
+#include <libbb.h>
+
+#ifdef __GNO__
+/* We use our own implementations of execv* because we need to
+ * do some things that libc's version doesn't:
+ * 1) Quote arguments containing spaces or tabs
+ * 2) Execute shell scripts in a shell (TODO)
+ */
+ 
+ /* Note that this expects environ to be initialized.  
+  * Also, if envp != environ, it will update the environment of this process
+  * (and the one it's forked from, if any, unless there's been an environPush).
+  */
+int execve(const char *path, char *const *argv, char *const *envp)
+{
+	int result;
+	char *args;
+	
+	size_t argslen = 0;
+	int i;
+	char *nextarg;
+	
+	for (i = 0; argv[i] != NULL; i++) {
+		/* 3 bytes extra for space (or terminating 0) and possible quotes */
+		argslen += strlen(argv[i]) + 3;
+	}
+	
+	nextarg = args = malloc(argslen);
+	if (args == NULL) {
+		free(path);
+		errno = ENOMEM;
+		return -1;
+	}
+	
+	/* Copy arguments into a single string, quoting ones that contain spaces
+	 * or tabs.  This approach won't give the right result in all cases
+	 * (e.g. when the argument starts with " or contains both spaces and "),
+	 * but it's about the best we can do, since we're dependent on the 
+	 * argument-parsing code in the target program.
+	 */
+	for (i = 0; argv[i] != NULL; i++) {
+		bool has_space = (strpbrk(argv[i], " \t") != NULL);
+
+		if (has_space)
+			*nextarg++ = '"';
+		strcpy(nextarg, argv[i]);
+		nextarg += strlen(argv[i]);
+		if (has_space)
+			*nextarg++ = '"';
+		*nextarg++ = ' ';
+	}
+	*(nextarg - 1) = 0;
+	
+	/* Clear environment and then rebuild it, if necessary. */
+	if (envp != environ) {
+		while (environ[0] != NULL)
+			bb_unsetenv(environ[0]);
+		if (buildEnv(envp) != 0)
+			return -1;
+	}
+	
+	result = _execve(path, args);
+	
+	/* error case */
+	free(args);
+	return result;
+} 
+
+int execv(const char *path, char *const *argv)
+{
+	return execve(path, argv, environ);
+}
+ 
+int execvp(const char *file, char *const *argv)
+{
+	int result;
+	char *path;
+	
+	path = buildPath(file);
+	if (path == NULL) {
+		errno = ENOENT;
+		return -1;
+	}
+	
+	result = execve(path, argv, environ);
+	
+	/* error case */
+	free(path);
+	return result;
+}
+#endif

shell/hush.c

@@ -6746,69 +6746,6 @@ static void exec_builtin(char ***to_free,
 }
 
 
-#ifdef __GNO__
-/* We use our own implementation of execvp because we need to
- * do some things that libc's version doesn't:
- * 1) Quote arguments containing spaces or tabs
- * 2) Execute shell scripts in a shell (TODO)
- */
-#define execvp execvp_gno
-static int execvp_gno(const char *file, char *const argv[])
-{
-	int result;
-	char *args;
-	char *path;
-	
-	size_t argslen = 0;
-	int i;
-	char *nextarg;
-	
-	path = buildPath(file);
-	if (path == NULL) {
-		errno = ENOENT;
-		return -1;
-	}
-	
-	for (i = 0; argv[i] != NULL; i++) {
-		/* 3 bytes extra for space (or terminating 0) and possible quotes */
-		argslen += strlen(argv[i]) + 3;
-	}
-	
-	nextarg = args = malloc(argslen);
-	if (args == NULL) {
-		free(path);
-		errno = ENOMEM;
-		return -1;
-	}
-	
-	/* Copy arguments into a single string, quoting ones that contain spaces
-	 * or tabs.  This approach won't give the right result in all cases
-	 * (e.g. when the argument starts with " or contains both spaces and "),
-	 * but it's about the best we can do, since we're dependent on the 
-	 * argument-parsing code in the target program.
-	 */
-	for (i = 0; argv[i] != NULL; i++) {
-		bool has_space = (strpbrk(argv[i], " \t") != NULL);
-
-		if (has_space)
-			*nextarg++ = '"';
-		strcpy(nextarg, argv[i]);
-		nextarg += strlen(argv[i]);
-		if (has_space)
-			*nextarg++ = '"';
-		*nextarg++ = ' ';
-	}
-	*(nextarg - 1) = 0;
-	
-	result = _execve(path, args);
-	
-	/* error case */
-	free(path);
-	free(args);
-	return result;
-}
-#endif
-
 static void execvp_or_die(char **argv) NORETURN;
 static void execvp_or_die(char **argv)
 {