Migrate exec function to C++ arrays

native/jni/daemon/bootstages.c

@@ -115,29 +115,15 @@ static struct node_entry *insert_child(struct node_entry *p, struct node_entry *
  * setenvs *
  ***********/
 
-static void set_path(struct vector *v) {
+static void set_path() {
 	char buffer[512];
-	for (int i = 0; environ[i]; ++i) {
+	sprintf(buffer, BBPATH ":%s", getenv("PATH"));
-		if (strncmp(environ[i], "PATH=", 5) == 0) {
+	setenv("PATH", buffer, 1);
-			sprintf(buffer, "PATH="BBPATH":%s", environ[i] + 5);
-			vec_push_back(v, strdup(buffer));
-		} else {
-			vec_push_back(v, strdup(environ[i]));
-		}
-	}
-	vec_push_back(v, NULL);
 }
 
-static void set_mirror_path(struct vector *v) {
+static void set_mirror_path() {
-	for (int i = 0; environ[i]; ++i) {
+	setenv("PATH", BBPATH ":/sbin:" MIRRDIR "/system/bin:"
-		if (strncmp(environ[i], "PATH=", 5) == 0) {
+				   MIRRDIR "/system/xbin:" MIRRDIR "/vendor/bin", 1);
-			vec_push_back(v, strdup("PATH="BBPATH":/sbin:"MIRRDIR"/system/bin:"
-									MIRRDIR"/system/xbin:"MIRRDIR"/vendor/bin"));
-		} else {
-			vec_push_back(v, strdup(environ[i]));
-		}
-	}
-	vec_push_back(v, NULL);
 }
 
 /***********

native/jni/daemon/log_daemon.c

@@ -82,7 +82,7 @@ static void *logcat_thread(void *args) {
 	char line[4096];
 	while (1) {
 		// Start logcat
-		log_pid = exec_array(0, &log_fd, NULL, (char **) vec_entry(&log_cmd));
+		log_pid = exec_array(0, &log_fd, NULL, (const char **) vec_entry(&log_cmd));
 		FILE *logs = fdopen(log_fd, "r");
 		while (fgets(line, sizeof(line), logs)) {
 			if (line[0] == '-')
@@ -103,7 +103,7 @@ static void *logcat_thread(void *args) {
 
 		LOGI("magisklogd: logcat output EOF");
 		// Clear buffer
-		log_pid = exec_array(0, NULL, NULL, (char **) vec_entry(&clear_cmd));
+		log_pid = exec_array(0, NULL, NULL, (const char **) vec_entry(&clear_cmd));
 		waitpid(log_pid, NULL, 0);
 	}
 }

native/jni/utils/include/array.h

@@ -125,6 +125,10 @@ public:
 		qsort(_data, _size, sizeof(T), compare);
 	}
 
+	T* data() { return _data; }
+
+	const T* data() const { return _data; }
+
 	// void reserve(size_t n) { ... }
 	// void resize(size_t n) { ... }
 

native/jni/utils/include/utils.h

@@ -90,9 +90,9 @@ int file_to_vector(const char* filename, struct vector *v);
 int vector_to_file(const char* filename, struct vector *v);
 ssize_t fdgets(char *buf, size_t size, int fd);
 int is_num(const char *s);
-int exec_array(int err, int *fd, void (*setenv)(struct vector *), char *const *argv);
+int exec_array(int err, int *fd, void (*cb)(void), const char *argv[]);
-int exec_command(int err, int *fd, void (*setenv)(struct vector*), const char *argv0, ...);
+int exec_command(int err, int *fd, void (*cb)(void), const char *argv0, ...);
-int exec_command_sync(char *const argv0, ...);
+int exec_command_sync(const char *argv0, ...);
 int switch_mnt_ns(int pid);
 int fork_dont_care();
 void gen_rand_str(char *buf, int len);

native/jni/utils/legacy.c

@@ -5,93 +5,6 @@
 #include "utils.h"
 #include "logging.h"
 
-/*
-   fd == NULL -> Ignore output
-  *fd < 0     -> Open pipe and set *fd to the read end
-  *fd >= 0    -> STDOUT (or STDERR) will be redirected to *fd
-  *setenv     -> A callback function which sets up a vector of environment variables
-*/
-int exec_array(int err, int *fd, void (*setenv)(struct vector *), char *const *argv) {
-	int pipefd[2], writeEnd = -1;
-
-	if (fd) {
-		if (*fd < 0) {
-			if (xpipe2(pipefd, O_CLOEXEC) == -1)
-				return -1;
-			writeEnd = pipefd[1];
-		} else {
-			writeEnd = *fd;
-		}
-	}
-
-	// Setup environment
-	char **envp;
-	struct vector env;
-	vec_init(&env);
-	if (setenv) {
-		setenv(&env);
-		envp = (char **) vec_entry(&env);
-	} else {
-		extern char **environ;
-		envp = environ;
-	}
-
-	int pid = xfork();
-	if (pid != 0) {
-		if (fd && *fd < 0) {
-			// Give the read end and close write end
-			*fd = pipefd[0];
-			close(pipefd[1]);
-		}
-		vec_deep_destroy(&env);
-		return pid;
-	}
-
-	if (fd) {
-		xdup2(writeEnd, STDOUT_FILENO);
-		if (err)
-			xdup2(writeEnd, STDERR_FILENO);
-	}
-
-	environ = envp;
-	execvp(argv[0], argv);
-	PLOGE("execvp %s", argv[0]);
-	return -1;
-}
-
-static int v_exec_command(int err, int *fd, void (*setenv)(struct vector*), const char *argv0, va_list argv) {
-	// Collect va_list into vector
-	struct vector args;
-	vec_init(&args);
-	vec_push_back(&args, strdup(argv0));
-	for (void *arg = va_arg(argv, void*); arg; arg = va_arg(argv, void*))
-		vec_push_back(&args, strdup(arg));
-	vec_push_back(&args, NULL);
-	int pid = exec_array(err, fd, setenv, (char **) vec_entry(&args));
-	vec_deep_destroy(&args);
-	return pid;
-}
-
-int exec_command_sync(char *const argv0, ...) {
-	va_list argv;
-	va_start(argv, argv0);
-	int pid, status;
-	pid = v_exec_command(0, NULL, NULL, argv0, argv);
-	va_end(argv);
-	if (pid < 0)
-		return pid;
-	waitpid(pid, &status, 0);
-	return WEXITSTATUS(status);
-}
-
-int exec_command(int err, int *fd, void (*setenv)(struct vector*), const char *argv0, ...) {
-	va_list argv;
-	va_start(argv, argv0);
-	int pid = v_exec_command(err, fd, setenv, argv0, argv);
-	va_end(argv);
-	return pid;
-}
-
 /* All the string should be freed manually!! */
 int file_to_vector(const char* filename, struct vector *v) {
 	if (access(filename, R_OK) != 0)

native/jni/utils/misc.cpp

@@ -193,3 +193,78 @@ ssize_t __getline(char **lineptr, size_t *n, FILE *stream) {
 int __fsetxattr(int fd, const char *name, const void *value, size_t size, int flags) {
 	return (int) syscall(__NR_fsetxattr, fd, name, value, size, flags);
 }
+
+/*
+   fd == NULL -> Ignore output
+  *fd < 0     -> Open pipe and set *fd to the read end
+  *fd >= 0    -> STDOUT (or STDERR) will be redirected to *fd
+  *cb         -> A callback function which calls after forking
+*/
+int exec_array(int err, int *fd, void (*cb)(void), const char *argv[]) {
+	int pipefd[2], write_end = -1;
+
+	if (fd) {
+		if (*fd < 0) {
+			if (xpipe2(pipefd, O_CLOEXEC) == -1)
+				return -1;
+			write_end = pipefd[1];
+		} else {
+			write_end = *fd;
+		}
+	}
+
+	int pid = xfork();
+	if (pid != 0) {
+		if (fd && *fd < 0) {
+			// Give the read end and close write end
+			*fd = pipefd[0];
+			close(pipefd[1]);
+		}
+		return pid;
+	}
+
+	if (fd) {
+		xdup2(write_end, STDOUT_FILENO);
+		if (err)
+			xdup2(write_end, STDERR_FILENO);
+	}
+
+	// Setup environment
+	if (cb)
+		cb();
+
+	execvp(argv[0], (char **) argv);
+	PLOGE("execvp %s", argv[0]);
+	return -1;
+}
+
+static int v_exec_command(int err, int *fd, void (*cb)(void), const char *argv0, va_list argv) {
+	// Collect va_list into vector
+	Array<const char *> args;
+	args.push_back(argv0);
+	for (const char *arg = va_arg(argv, char*); arg; arg = va_arg(argv, char*))
+		args.push_back(arg);
+	args.push_back(nullptr);
+	int pid = exec_array(err, fd, cb, args.data());
+	return pid;
+}
+
+int exec_command_sync(const char *argv0, ...) {
+	va_list argv;
+	va_start(argv, argv0);
+	int pid, status;
+	pid = v_exec_command(0, NULL, NULL, argv0, argv);
+	va_end(argv);
+	if (pid < 0)
+		return pid;
+	waitpid(pid, &status, 0);
+	return WEXITSTATUS(status);
+}
+
+int exec_command(int err, int *fd, void (*cb)(void), const char *argv0, ...) {
+	va_list argv;
+	va_start(argv, argv0);
+	int pid = v_exec_command(err, fd, cb, argv0, argv);
+	va_end(argv);
+	return pid;
+}