From a6113cb070b460f715e3b677ab463b258fa3a3e0 Mon Sep 17 00:00:00 2001 From: Jonas Fonseca Date: Fri, 9 Jan 2009 22:21:44 -0500 Subject: [PATCH] IO API: use fork+exec --- tig.c | 156 ++++++++++++++++++++++++++-------------------------------- 1 file changed, 69 insertions(+), 87 deletions(-) diff --git a/tig.c b/tig.c index 1fd4bc9..eab037f 100644 --- a/tig.c +++ b/tig.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include #include @@ -144,7 +145,6 @@ enum format_flags { FORMAT_NONE /* No replacement should be performed. */ }; -static bool format_command(char dst[], const char *src[], enum format_flags flags); static bool format_argv(const char *dst[], const char *src[], enum format_flags flags); struct int_map { @@ -270,48 +270,6 @@ suffixcmp(const char *str, int slen, const char *suffix) return suffixlen < len ? strcmp(str + len - suffixlen, suffix) : -1; } -/* Shell quoting - * - * NOTE: The following is a slightly modified copy of the git project's shell - * quoting routines found in the quote.c file. - * - * Help to copy the thing properly quoted for the shell safety. any single - * quote is replaced with '\'', any exclamation point is replaced with '\!', - * and the whole thing is enclosed in a - * - * E.g. - * original sq_quote result - * name ==> name ==> 'name' - * a b ==> a b ==> 'a b' - * a'b ==> a'\''b ==> 'a'\''b' - * a!b ==> a'\!'b ==> 'a'\!'b' - */ - -static size_t -sq_quote(char buf[SIZEOF_STR], size_t bufsize, const char *src) -{ - char c; - -#define BUFPUT(x) do { if (bufsize < SIZEOF_STR) buf[bufsize++] = (x); } while (0) - - BUFPUT('\''); - while ((c = *src++)) { - if (c == '\'' || c == '!') { - BUFPUT('\''); - BUFPUT('\\'); - BUFPUT(c); - BUFPUT('\''); - } else { - BUFPUT(c); - } - } - BUFPUT('\''); - - if (bufsize < SIZEOF_STR) - buf[bufsize] = 0; - - return bufsize; -} static bool argv_from_string(const char *argv[SIZEOF_ARG], int *argc, char *cmd) @@ -359,7 +317,7 @@ enum io_type { struct io { enum io_type type; /* The requested type of pipe. */ const char *dir; /* Directory from which to execute. */ - FILE *pid; /* Pipe for reading or writing. */ + pid_t pid; /* Pipe for reading or writing. */ int pipe; /* Pipe end for reading or writing. */ int error; /* Error status. */ const char *argv[SIZEOF_ARG]; /* Shell command arguments. */ @@ -374,7 +332,7 @@ static void reset_io(struct io *io) { io->pipe = -1; - io->pid = NULL; + io->pid = 0; io->buf = io->bufpos = NULL; io->bufalloc = io->bufsize = 0; io->error = 0; @@ -405,42 +363,89 @@ io_open(struct io *io, const char *name) return io->pipe != -1; } +static bool +kill_io(struct io *io) +{ + return kill(io->pid, SIGKILL) != -1; +} + static bool done_io(struct io *io) { - free(io->buf); - if (io->type == IO_FD) + pid_t pid = io->pid; + + if (io->pipe != -1) close(io->pipe); - else if (io->type == IO_RD || io->type == IO_WR) - pclose(io->pid); + free(io->buf); reset_io(io); + + while (pid > 0) { + int status; + pid_t waiting = waitpid(pid, &status, 0); + + if (waiting < 0) { + if (errno == EINTR) + continue; + report("waitpid failed (%s)", strerror(errno)); + return FALSE; + } + + return waiting == pid && + !WIFSIGNALED(status) && + WIFEXITED(status) && + !WEXITSTATUS(status); + } + return TRUE; } static bool start_io(struct io *io) { - char buf[SIZEOF_STR * 2]; - size_t bufpos = 0; + int pipefds[2] = { -1, -1 }; if (io->type == IO_FD) return TRUE; - if (io->dir && *io->dir && - !string_format_from(buf, &bufpos, "cd %s;", io->dir)) + if ((io->type == IO_RD || io->type == IO_WR) && + pipe(pipefds) < 0) return FALSE; - if (!format_command(buf + bufpos, io->argv, FORMAT_NONE)) - return FALSE; + if ((io->pid = fork())) { + if (pipefds[!(io->type == IO_WR)] != -1) + close(pipefds[!(io->type == IO_WR)]); + if (io->pid != -1) { + io->pipe = pipefds[!!(io->type == IO_WR)]; + return TRUE; + } + + } else { + if (io->type != IO_FG) { + int devnull = open("/dev/null", O_RDWR); + int readfd = io->type == IO_WR ? pipefds[0] : devnull; + int writefd = io->type == IO_RD ? pipefds[1] : devnull; + + dup2(readfd, STDIN_FILENO); + dup2(writefd, STDOUT_FILENO); + dup2(devnull, STDERR_FILENO); + + close(devnull); + if (pipefds[0] != -1) + close(pipefds[0]); + if (pipefds[1] != -1) + close(pipefds[1]); + } - if (io->type == IO_FG || io->type == IO_BG) - return system(buf) == 0; + if (io->dir && *io->dir && chdir(io->dir) == -1) + die("Failed to change directory: %s", strerror(errno)); - io->pid = popen(buf, io->type == IO_RD ? "r" : "w"); - if (!io->pid) - return FALSE; - io->pipe = fileno(io->pid); - return io->pipe != -1; + execvp(io->argv[0], (char *const*) io->argv); + die("Failed to execute program: %s", strerror(errno)); + } + + if (pipefds[!!(io->type == IO_WR)] != -1) + close(pipefds[!!(io->type == IO_WR)]); + return FALSE; } static bool @@ -2554,31 +2559,6 @@ format_argv(const char *dst_argv[], const char *src_argv[], enum format_flags fl return src_argv[argc] == NULL; } -static bool -format_command(char dst[], const char *src_argv[], enum format_flags flags) -{ - const char *dst_argv[SIZEOF_ARG * 2] = { NULL }; - int bufsize = 0; - int argc; - - if (!format_argv(dst_argv, src_argv, flags)) { - free_argv(dst_argv); - return FALSE; - } - - for (argc = 0; dst_argv[argc] && bufsize < SIZEOF_STR; argc++) { - if (bufsize > 0) - dst[bufsize++] = ' '; - bufsize = sq_quote(dst, bufsize, dst_argv[argc]); - } - - if (bufsize < SIZEOF_STR) - dst[bufsize] = 0; - free_argv(dst_argv); - - return src_argv[argc] == NULL && bufsize < SIZEOF_STR; -} - static void end_update(struct view *view, bool force) { @@ -2588,6 +2568,8 @@ end_update(struct view *view, bool force) if (!force) return; set_nonblocking_input(FALSE); + if (force) + kill_io(view->pipe); done_io(view->pipe); view->pipe = NULL; } -- 2.32.0.93.g670b81a890