From 64426f1a89450a0f79b723a4d966f7f9c7492c60 Mon Sep 17 00:00:00 2001 From: Tavian Barnes Date: Sat, 12 Mar 2022 22:43:10 -0500 Subject: Don't shadow standard headers @italic on the AUR stated that bfs from the AUR fails to build on Manjaro. From the build log, it seems like doesn't get included properly. I assume it's picking up ./time.h instead. I couldn't reproduce the build issue in the default configuration, but it does fail with EXTRA_CFLAGS="-I." which isn't good. So rename everything with an x prefix to stop clashing. Link: https://aur.archlinux.org/packages/bfs#comment-856102 Link: https://paste.rs/eqR --- spawn.c | 318 ---------------------------------------------------------------- 1 file changed, 318 deletions(-) delete mode 100644 spawn.c (limited to 'spawn.c') diff --git a/spawn.c b/spawn.c deleted file mode 100644 index 31f9897..0000000 --- a/spawn.c +++ /dev/null @@ -1,318 +0,0 @@ -/**************************************************************************** - * bfs * - * Copyright (C) 2018-2022 Tavian Barnes * - * * - * Permission to use, copy, modify, and/or distribute this software for any * - * purpose with or without fee is hereby granted. * - * * - * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * - * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * - * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * - * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * - * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * - * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * - * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * - ****************************************************************************/ - -#include "spawn.h" -#include "util.h" -#include -#include -#include -#include -#include -#include -#include - -/** - * Types of spawn actions. - */ -enum bfs_spawn_op { - BFS_SPAWN_CLOSE, - BFS_SPAWN_DUP2, - BFS_SPAWN_FCHDIR, - BFS_SPAWN_SETRLIMIT, -}; - -/** - * A spawn action. - */ -struct bfs_spawn_action { - struct bfs_spawn_action *next; - - enum bfs_spawn_op op; - int in_fd; - int out_fd; - int resource; - struct rlimit rlimit; -}; - -int bfs_spawn_init(struct bfs_spawn *ctx) { - ctx->flags = 0; - ctx->actions = NULL; - ctx->tail = &ctx->actions; - return 0; -} - -int bfs_spawn_destroy(struct bfs_spawn *ctx) { - struct bfs_spawn_action *action = ctx->actions; - while (action) { - struct bfs_spawn_action *next = action->next; - free(action); - action = next; - } - return 0; -} - -int bfs_spawn_setflags(struct bfs_spawn *ctx, enum bfs_spawn_flags flags) { - ctx->flags = flags; - return 0; -} - -/** Add a spawn action to the chain. */ -static struct bfs_spawn_action *bfs_spawn_add(struct bfs_spawn *ctx, enum bfs_spawn_op op) { - struct bfs_spawn_action *action = malloc(sizeof(*action)); - if (action) { - action->next = NULL; - action->op = op; - action->in_fd = -1; - action->out_fd = -1; - - *ctx->tail = action; - ctx->tail = &action->next; - } - return action; -} - -int bfs_spawn_addclose(struct bfs_spawn *ctx, int fd) { - if (fd < 0) { - errno = EBADF; - return -1; - } - - struct bfs_spawn_action *action = bfs_spawn_add(ctx, BFS_SPAWN_CLOSE); - if (action) { - action->out_fd = fd; - return 0; - } else { - return -1; - } -} - -int bfs_spawn_adddup2(struct bfs_spawn *ctx, int oldfd, int newfd) { - if (oldfd < 0 || newfd < 0) { - errno = EBADF; - return -1; - } - - struct bfs_spawn_action *action = bfs_spawn_add(ctx, BFS_SPAWN_DUP2); - if (action) { - action->in_fd = oldfd; - action->out_fd = newfd; - return 0; - } else { - return -1; - } -} - -int bfs_spawn_addfchdir(struct bfs_spawn *ctx, int fd) { - if (fd < 0) { - errno = EBADF; - return -1; - } - - struct bfs_spawn_action *action = bfs_spawn_add(ctx, BFS_SPAWN_FCHDIR); - if (action) { - action->in_fd = fd; - return 0; - } else { - return -1; - } -} - -int bfs_spawn_addsetrlimit(struct bfs_spawn *ctx, int resource, const struct rlimit *rl) { - struct bfs_spawn_action *action = bfs_spawn_add(ctx, BFS_SPAWN_SETRLIMIT); - if (action) { - action->resource = resource; - action->rlimit = *rl; - return 0; - } else { - return -1; - } -} - -/** Actually exec() the new process. */ -static void bfs_spawn_exec(const char *exe, const struct bfs_spawn *ctx, char **argv, char **envp, int pipefd[2]) { - int error; - const struct bfs_spawn_action *actions = ctx ? ctx->actions : NULL; - - xclose(pipefd[0]); - - for (const struct bfs_spawn_action *action = actions; action; action = action->next) { - // Move the error-reporting pipe out of the way if necessary... - if (action->out_fd == pipefd[1]) { - int fd = dup_cloexec(pipefd[1]); - if (fd < 0) { - goto fail; - } - xclose(pipefd[1]); - pipefd[1] = fd; - } - - // ... and pretend the pipe doesn't exist - if (action->in_fd == pipefd[1]) { - errno = EBADF; - goto fail; - } - - switch (action->op) { - case BFS_SPAWN_CLOSE: - if (close(action->out_fd) != 0) { - goto fail; - } - break; - case BFS_SPAWN_DUP2: - if (dup2(action->in_fd, action->out_fd) < 0) { - goto fail; - } - break; - case BFS_SPAWN_FCHDIR: - if (fchdir(action->in_fd) != 0) { - goto fail; - } - break; - case BFS_SPAWN_SETRLIMIT: - if (setrlimit(action->resource, &action->rlimit) != 0) { - goto fail; - } - break; - } - } - - execve(exe, argv, envp); - -fail: - error = errno; - - // In case of a write error, the parent will still see that we exited - // unsuccessfully, but won't know why - (void) xwrite(pipefd[1], &error, sizeof(error)); - - xclose(pipefd[1]); - _Exit(127); -} - -pid_t bfs_spawn(const char *exe, const struct bfs_spawn *ctx, char **argv, char **envp) { - extern char **environ; - if (!envp) { - envp = environ; - } - - enum bfs_spawn_flags flags = ctx ? ctx->flags : 0; - char *resolved = NULL; - if (flags & BFS_SPAWN_USEPATH) { - exe = resolved = bfs_spawn_resolve(exe); - if (!resolved) { - return -1; - } - } - - // Use a pipe to report errors from the child - int pipefd[2]; - if (pipe_cloexec(pipefd) != 0) { - free(resolved); - return -1; - } - - pid_t pid = fork(); - if (pid < 0) { - close_quietly(pipefd[1]); - close_quietly(pipefd[0]); - free(resolved); - return -1; - } else if (pid == 0) { - // Child - bfs_spawn_exec(exe, ctx, argv, envp, pipefd); - } - - // Parent - xclose(pipefd[1]); - free(resolved); - - int error; - ssize_t nbytes = xread(pipefd[0], &error, sizeof(error)); - xclose(pipefd[0]); - if (nbytes == sizeof(error)) { - int wstatus; - waitpid(pid, &wstatus, 0); - errno = error; - return -1; - } - - return pid; -} - -char *bfs_spawn_resolve(const char *exe) { - if (strchr(exe, '/')) { - return strdup(exe); - } - - const char *path = getenv("PATH"); - - char *confpath = NULL; - if (!path) { - path = confpath = xconfstr(_CS_PATH); - if (!path) { - return NULL; - } - } - - size_t cap = 0; - char *ret = NULL; - while (true) { - const char *end = strchr(path, ':'); - size_t len = end ? (size_t)(end - path) : strlen(path); - - // POSIX 8.3: "A zero-length prefix is a legacy feature that - // indicates the current working directory." - if (len == 0) { - path = "."; - len = 1; - } - - size_t total = len + 1 + strlen(exe) + 1; - if (cap < total) { - char *grown = realloc(ret, total); - if (!grown) { - goto fail; - } - ret = grown; - cap = total; - } - - memcpy(ret, path, len); - if (ret[len - 1] != '/') { - ret[len++] = '/'; - } - strcpy(ret + len, exe); - - if (xfaccessat(AT_FDCWD, ret, X_OK) == 0) { - break; - } - - if (!end) { - errno = ENOENT; - goto fail; - } - - path = end + 1; - } - - free(confpath); - return ret; - -fail: - free(confpath); - free(ret); - return NULL; -} -- cgit v1.2.3