// POSIX implementation of OS functions #include "os.h" #include "util.h" #include #include #include #include #include #include #include #include #include #include #include #include static FsType statbuf_path_type(const struct stat *statbuf) { if (S_ISREG(statbuf->st_mode)) return FS_FILE; if (S_ISDIR(statbuf->st_mode)) return FS_DIRECTORY; return FS_OTHER; } FsType fs_path_type(const char *path) { struct stat statbuf = {0}; if (stat(path, &statbuf) != 0) return FS_NON_EXISTENT; return statbuf_path_type(&statbuf); } FsPermission fs_path_permission(const char *path) { FsPermission perm = 0; if (access(path, R_OK) == 0) perm |= FS_PERMISSION_READ; if (access(path, W_OK) == 0) perm |= FS_PERMISSION_WRITE; return perm; } bool fs_file_exists(const char *path) { return fs_path_type(path) == FS_FILE; } FsDirectoryEntry **fs_list_directory(const char *dirname) { FsDirectoryEntry **entries = NULL; DIR *dir = opendir(dirname); if (dir) { struct dirent *ent; size_t nentries = 0; int fd = dirfd(dir); if (fd != -1) { while (readdir(dir)) ++nentries; rewinddir(dir); entries = (FsDirectoryEntry **)calloc(nentries+1, sizeof *entries); if (entries) { size_t idx = 0; while ((ent = readdir(dir))) { const char *filename = ent->d_name; size_t len = strlen(filename); FsDirectoryEntry *entry = (FsDirectoryEntry *)calloc(1, sizeof *entry + len + 1); if (!entry) break; memcpy(entry->name, filename, len); switch (ent->d_type) { case DT_REG: entry->type = FS_FILE; break; case DT_DIR: entry->type = FS_DIRECTORY; break; case DT_LNK: // we need to dereference the link case DT_UNKNOWN: { // information not available directly from dirent, we need to get it ourselves struct stat statbuf = {0}; fstatat(fd, filename, &statbuf, 0); entry->type = statbuf_path_type(&statbuf); } break; default: entry->type = FS_OTHER; } if (idx < nentries) // this could actually fail if someone creates files between calculating nentries and here. entries[idx++] = entry; } } } closedir(dir); } return entries; } int fs_mkdir(const char *path) { if (mkdir(path, 0755) == 0) { // directory created successfully return 1; } else if (errno == EEXIST) { struct stat statbuf = {0}; if (stat(path, &statbuf) == 0) { if (S_ISDIR(statbuf.st_mode)) { // already exists, and it's a directory return 0; } else { // already exists, but not a directory return -1; } } else { return -1; } } else { return -1; } } int os_get_cwd(char *buf, size_t buflen) { assert(buf && buflen); if (getcwd(buf, buflen)) { return 1; } else if (errno == ERANGE) { return 0; } else { return -1; } } int os_rename_overwrite(const char *oldname, const char *newname) { return rename(oldname, newname) == 0 ? 0 : -1; } struct timespec time_last_modified(const char *filename) { struct stat statbuf = {0}; stat(filename, &statbuf); return statbuf.st_mtim; } struct timespec time_get(void) { struct timespec ts = {0}; clock_gettime(CLOCK_REALTIME, &ts); return ts; } void time_sleep_ns(u64 ns) { struct timespec rem = {0}, req = { (time_t)(ns / 1000000000), (long)(ns % 1000000000) }; while (nanosleep(&req, &rem) == EINTR) // sleep interrupted by signal req = rem; } struct Process { pid_t pid; int stdout_pipe; // only applicable if separate_stderr was specified. int stderr_pipe; int stdin_pipe; char error[64]; }; int process_get_id(void) { return getpid(); } static void set_nonblocking(int fd) { fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK); } Process *process_run_ex(const char *command, const ProcessSettings *settings) { Process *proc = calloc(1, sizeof *proc); int stdin_pipe[2] = {0}, stdout_pipe[2] = {0}, stderr_pipe[2] = {0}; if (pipe(stdin_pipe) != 0) { strbuf_printf(proc->error, "%s", strerror(errno)); return proc; } if (pipe(stdout_pipe) != 0) { strbuf_printf(proc->error, "%s", strerror(errno)); close(stdin_pipe[0]); close(stdin_pipe[1]); return proc; } if (settings->separate_stderr) { if (pipe(stderr_pipe) != 0) { strbuf_printf(proc->error, "%s", strerror(errno)); close(stdin_pipe[0]); close(stdin_pipe[1]); close(stdout_pipe[0]); close(stdout_pipe[1]); return proc; } } pid_t pid = fork(); if (pid == 0) { // child process chdir(settings->working_directory); // put child in its own group. it will be in this group with all of its descendents, // so by killing everything in the group, we kill all the descendents of this process. // if we didn't do this, we would just be killing the sh process in process_kill. setpgid(0, 0); // pipe stuff dup2(stdout_pipe[1], STDOUT_FILENO); if (stderr_pipe[1]) dup2(stderr_pipe[1], STDERR_FILENO); else dup2(stdout_pipe[1], STDERR_FILENO); dup2(stdin_pipe[0], STDIN_FILENO); // don't need these file descriptors anymore close(stdin_pipe[0]); close(stdin_pipe[1]); close(stdout_pipe[0]); close(stdout_pipe[1]); if (stderr_pipe[0]) { close(stderr_pipe[0]); close(stderr_pipe[1]); } char *program = "/bin/sh"; char *argv[] = {program, "-c", (char *)command, NULL}; if (execv(program, argv) == -1) { dprintf(STDERR_FILENO, "%s: %s\n", program, strerror(errno)); exit(127); } } else if (pid > 0) { // parent process // we're reading from (the child's) stdout/stderr and writing to stdin, // so we don't need the write end of the stdout pipe or the // read end of the stdin pipe. close(stdout_pipe[1]); if (stderr_pipe[1]) close(stderr_pipe[1]); close(stdin_pipe[0]); // set pipes to non-blocking set_nonblocking(stdout_pipe[0]); if (stderr_pipe[0]) set_nonblocking(stderr_pipe[0]); proc->pid = pid; proc->stdout_pipe = stdout_pipe[0]; if (stderr_pipe[0]) proc->stderr_pipe = stderr_pipe[0]; proc->stdin_pipe = stdin_pipe[1]; } return proc; } Process *process_run(const char *command) { const ProcessSettings settings = {0}; return process_run_ex(command, &settings); } const char *process_geterr(Process *p) { if (!p) return "no such process"; return *p->error ? p->error : NULL; } static long long write_fd(int fd, char *error, size_t error_size, const char *data, size_t size) { if (size > LLONG_MAX) { str_printf(error, error_size, "too much data to write"); return -2; } size_t so_far = 0; while (so_far < size) { ssize_t bytes_written = write(fd, data + so_far, size - so_far); if (bytes_written >= 0) { so_far += (size_t)bytes_written; } else if (errno == EAGAIN || errno == EWOULDBLOCK) { return (long long)so_far; } else if (errno == EPIPE) { return -1; } else { str_printf(error, error_size, "write failed: %s", strerror(errno)); return -2; } } return (long long)size; } static long long read_fd(int fd, char *error, size_t error_size, char *data, size_t size) { if (size > LLONG_MAX) { str_printf(error, error_size, "Too much data to read."); return -2; } size_t so_far = 0; while (so_far < size) { ssize_t bytes_read = read(fd, data + so_far, size - so_far); if (bytes_read > 0) { so_far += (size_t)bytes_read; } else if (bytes_read == 0) { return (long long)so_far; } else if (errno == EAGAIN || errno == EWOULDBLOCK) { return so_far == 0 ? -1 : (long long)so_far; } else if (errno == EPIPE) { return -1; } else { str_printf(error, error_size, "read failed: %s", strerror(errno)); return -2; } } return (long long)size; } long long process_write(Process *proc, const char *data, size_t size) { if (!proc) { assert(0); return -2; } if (!proc->stdin_pipe) { // check that process hasn't been killed strbuf_printf(proc->error, "Process terminated"); return -2; } return write_fd(proc->stdin_pipe, proc->error, sizeof proc->error, data, size); } static long long process_read_fd(Process *proc, int fd, char *data, size_t size) { if (!fd) { // check that process hasn't been killed strbuf_printf(proc->error, "Process terminated"); return -2; } return read_fd(fd, proc->error, sizeof proc->error, data, size); } long long process_read(Process *proc, char *data, size_t size) { if (!proc) { assert(0); return 0; } return process_read_fd(proc, proc->stdout_pipe, data, size); } long long process_read_stderr(Process *proc, char *data, size_t size) { if (!proc) { assert(0); return 0; } return process_read_fd(proc, proc->stderr_pipe, data, size); } static void process_close_pipes(Process *proc) { if (proc->stdin_pipe) close(proc->stdin_pipe); if (proc->stdout_pipe) close(proc->stdout_pipe); if (proc->stderr_pipe) close(proc->stderr_pipe); proc->stdin_pipe = 0; proc->stdout_pipe = 0; proc->stderr_pipe = 0; proc->pid = 0; } void process_kill(Process **pproc) { Process *proc = *pproc; if (!proc) return; kill(-proc->pid, SIGKILL); // kill everything in process group // get rid of zombie process waitpid(proc->pid, NULL, 0); process_close_pipes(proc); free(proc); *pproc = NULL; } int process_check_status(Process **pproc, ProcessExitInfo *info) { Process *proc = *pproc; memset(info, 0, sizeof *info); if (!proc) { assert(0); strbuf_printf(info->message, "checked status twice"); return -1; } int wait_status = 0; int ret = waitpid(proc->pid, &wait_status, WNOHANG); if (ret == 0) { // process still running return 0; } else if (ret > 0) { if (WIFEXITED(wait_status)) { process_kill(pproc); int code = WEXITSTATUS(wait_status); info->exit_code = code; info->exited = true; if (code == 0) { strbuf_printf(info->message, "exited successfully"); return +1; } else { strbuf_printf(info->message, "exited with code %d", code); return -1; } } else if (WIFSIGNALED(wait_status)) { int signal = WTERMSIG(wait_status); info->signal = signal; info->signalled = true; process_close_pipes(proc); strbuf_printf(info->message, "terminated by signal %d", info->signal); return -1; } return 0; } else { // this process is gone or something? process_close_pipes(proc); strbuf_printf(info->message, "process ended unexpectedly"); return -1; } } bool open_with_default_application(const char *path) { const char *cmd = NULL; #if __linux__ cmd = "xdg-open"; #elif __APPLE__ cmd = "open"; #endif if (!cmd) return false; switch (fork()) { case 0: execlp(cmd, cmd, path, NULL); abort(); case -1: return false; default: return true; } } bool change_directory(const char *path) { return chdir(path) == 0; } struct Socket { int fd; char error[256]; }; Socket *socket_connect_tcp(const char *address, u16 port) { Socket *s = calloc(1, sizeof *s); if (!s) return NULL; if (!address) address = "127.0.0.1"; int fd = socket(AF_INET, SOCK_STREAM, 0); if (fd < 0) { strbuf_printf(s->error, "couldn't create socket (%s)", strerror(errno)); return s; } struct sockaddr_in addr = { .sin_family = AF_INET, .sin_port = htons(port), .sin_addr = {0}, .sin_zero = {0} }; if (inet_pton(AF_INET, address, &addr.sin_addr) <= 0) { strbuf_printf(s->error, "invalid address"); return s; } if (connect(fd, &addr, sizeof addr) < 0) { strbuf_printf(s->error, "couldn't connect to %u.%u.%u.%u:%u (%s)", address[0], address[1], address[2], address[3], port, strerror(errno)); } set_nonblocking(fd); s->fd = fd; return s; } const char *socket_get_error(Socket *socket) { return socket->error; } long long socket_read(Socket *s, char *data, size_t size) { if (s->fd <= 0) { strbuf_printf(s->error, "socket has been closed"); return -2; } return read_fd(s->fd, s->error, sizeof s->error, data, size); } long long socket_write(Socket *s, const char *data, size_t size) { if (s->fd <= 0) { strbuf_printf(s->error, "socket has been closed"); return -2; } return write_fd(s->fd, s->error, sizeof s->error, data, size); }