summaryrefslogtreecommitdiffstats
path: root/osdep
diff options
context:
space:
mode:
authorJames Ross-Gowan <rossymiles@gmail.com>2014-11-22 17:21:33 +1100
committerJames Ross-Gowan <rossymiles@gmail.com>2014-11-22 18:15:13 +1100
commitef0d1cddb6d1719b60933fd1dc00f938c095c00c (patch)
treec6ce0882254c12c4bc21e4442ffed382e6ea94b5 /osdep
parentb2d048440472c8b22abd1945e9ca2cfdfd27f2d0 (diff)
downloadmpv-ef0d1cddb6d1719b60933fd1dc00f938c095c00c.tar.bz2
mpv-ef0d1cddb6d1719b60933fd1dc00f938c095c00c.tar.xz
lua: subprocess: move to osdep/subprocess-{win,posix}.c
The subprocess code was already split into fairly general functions, separate from the Lua code. It's getting pretty big though, especially the Windows-specific parts, so move it into its own files.
Diffstat (limited to 'osdep')
-rw-r--r--osdep/subprocess-posix.c146
-rw-r--r--osdep/subprocess-win.c371
-rw-r--r--osdep/subprocess.h30
3 files changed, 547 insertions, 0 deletions
diff --git a/osdep/subprocess-posix.c b/osdep/subprocess-posix.c
new file mode 100644
index 0000000000..8dcc5f6304
--- /dev/null
+++ b/osdep/subprocess-posix.c
@@ -0,0 +1,146 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with mpv. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "osdep/subprocess.h"
+
+#include <spawn.h>
+#include <poll.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <errno.h>
+#include <signal.h>
+
+#include "osdep/io.h"
+#include "common/common.h"
+
+// Normally, this must be declared manually, but glibc is retarded.
+#ifndef __GLIBC__
+extern char **environ;
+#endif
+
+// A silly helper: automatically skips entries with negative FDs
+static int sparse_poll(struct pollfd *fds, int num_fds, int timeout)
+{
+ struct pollfd p_fds[10];
+ int map[10];
+ if (num_fds > MP_ARRAY_SIZE(p_fds))
+ return -1;
+ int p_num_fds = 0;
+ for (int n = 0; n < num_fds; n++) {
+ map[n] = -1;
+ if (fds[n].fd < 0)
+ continue;
+ map[n] = p_num_fds;
+ p_fds[p_num_fds++] = fds[n];
+ }
+ int r = poll(p_fds, p_num_fds, timeout);
+ for (int n = 0; n < num_fds; n++)
+ fds[n].revents = (map[n] < 0 && r >= 0) ? 0 : p_fds[map[n]].revents;
+ return r;
+}
+
+int mp_subprocess(char **args, struct mp_cancel *cancel, void *ctx,
+ subprocess_read_cb on_stdout, subprocess_read_cb on_stderr,
+ char **error)
+{
+ posix_spawn_file_actions_t fa;
+ bool fa_destroy = false;
+ int status = -1;
+ int p_stdout[2] = {-1, -1};
+ int p_stderr[2] = {-1, -1};
+ pid_t pid = -1;
+
+ if (mp_make_cloexec_pipe(p_stdout) < 0)
+ goto done;
+ if (mp_make_cloexec_pipe(p_stderr) < 0)
+ goto done;
+
+ if (posix_spawn_file_actions_init(&fa))
+ goto done;
+ fa_destroy = true;
+ // redirect stdout and stderr
+ if (posix_spawn_file_actions_adddup2(&fa, p_stdout[1], 1))
+ goto done;
+ if (posix_spawn_file_actions_adddup2(&fa, p_stderr[1], 2))
+ goto done;
+
+ if (posix_spawnp(&pid, args[0], &fa, NULL, args, environ)) {
+ pid = -1;
+ goto done;
+ }
+
+ close(p_stdout[1]);
+ p_stdout[1] = -1;
+ close(p_stderr[1]);
+ p_stderr[1] = -1;
+
+ int *read_fds[2] = {&p_stdout[0], &p_stderr[0]};
+ subprocess_read_cb read_cbs[2] = {on_stdout, on_stderr};
+
+ while (p_stdout[0] >= 0 || p_stderr[0] >= 0) {
+ struct pollfd fds[] = {
+ {.events = POLLIN, .fd = *read_fds[0]},
+ {.events = POLLIN, .fd = *read_fds[1]},
+ {.events = POLLIN, .fd = cancel ? mp_cancel_get_fd(cancel) : -1},
+ };
+ if (sparse_poll(fds, MP_ARRAY_SIZE(fds), -1) < 0 && errno != EINTR)
+ break;
+ for (int n = 0; n < 2; n++) {
+ if (fds[n].revents) {
+ char buf[4096];
+ ssize_t r = read(*read_fds[n], buf, sizeof(buf));
+ if (r < 0 && errno == EINTR)
+ continue;
+ if (r > 0 && read_cbs[n])
+ read_cbs[n](ctx, buf, r);
+ if (r <= 0) {
+ close(*read_fds[n]);
+ *read_fds[n] = -1;
+ }
+ }
+ }
+ if (fds[2].revents) {
+ kill(pid, SIGKILL);
+ break;
+ }
+ }
+
+ // Note: it can happen that a child process closes the pipe, but does not
+ // terminate yet. In this case, we would have to run waitpid() in
+ // a separate thread and use pthread_cancel(), or use other weird
+ // and laborious tricks. So this isn't handled yet.
+ while (waitpid(pid, &status, 0) < 0 && errno == EINTR) {}
+
+done:
+ if (fa_destroy)
+ posix_spawn_file_actions_destroy(&fa);
+ close(p_stdout[0]);
+ close(p_stdout[1]);
+ close(p_stderr[0]);
+ close(p_stderr[1]);
+
+ if (WIFEXITED(status) && WEXITSTATUS(status) != 127) {
+ *error = NULL;
+ status = WEXITSTATUS(status);
+ } else {
+ *error = WEXITSTATUS(status) == 127 ? "init" : "killed";
+ status = -1;
+ }
+
+ return status;
+}
diff --git a/osdep/subprocess-win.c b/osdep/subprocess-win.c
new file mode 100644
index 0000000000..04ea4ec3e4
--- /dev/null
+++ b/osdep/subprocess-win.c
@@ -0,0 +1,371 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with mpv. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define _WIN32_WINNT 0x0600
+#include "osdep/subprocess.h"
+
+#include <windows.h>
+#include <string.h>
+
+#include "osdep/io.h"
+#include "osdep/atomics.h"
+
+#include "talloc.h"
+#include "common/common.h"
+#include "misc/bstr.h"
+
+static void write_arg(bstr *cmdline, char *arg)
+{
+ // If the string doesn't have characters that need to be escaped, it's best
+ // to leave it alone for the sake of Windows programs that don't process
+ // quoted args correctly.
+ if (!strpbrk(arg, " \t\"")) {
+ bstr_xappend(NULL, cmdline, bstr0(arg));
+ return;
+ }
+
+ // If there are characters that need to be escaped, write a quoted string
+ bstr_xappend(NULL, cmdline, bstr0("\""));
+
+ // Escape the argument. To match the behavior of CommandLineToArgvW,
+ // backslashes are only escaped if they appear before a quote or the end of
+ // the string.
+ int num_slashes = 0;
+ for (int pos = 0; arg[pos]; pos++) {
+ switch (arg[pos]) {
+ case '\\':
+ // Count backslashes that appear in a row
+ num_slashes++;
+ break;
+ case '"':
+ bstr_xappend(NULL, cmdline, (struct bstr){arg, pos});
+
+ // Double preceding slashes
+ for (int i = 0; i < num_slashes; i++)
+ bstr_xappend(NULL, cmdline, bstr0("\\"));
+
+ // Escape the following quote
+ bstr_xappend(NULL, cmdline, bstr0("\\"));
+
+ arg += pos;
+ pos = 0;
+ num_slashes = 0;
+ break;
+ default:
+ num_slashes = 0;
+ }
+ }
+
+ // Write the rest of the argument
+ bstr_xappend(NULL, cmdline, bstr0(arg));
+
+ // Double slashes that appear at the end of the string
+ for (int i = 0; i < num_slashes; i++)
+ bstr_xappend(NULL, cmdline, bstr0("\\"));
+
+ bstr_xappend(NULL, cmdline, bstr0("\""));
+}
+
+// Convert an array of arguments to a properly escaped command-line string
+static wchar_t *write_cmdline(void *ctx, char **argv)
+{
+ bstr cmdline = {0};
+
+ for (int i = 0; argv[i]; i++) {
+ write_arg(&cmdline, argv[i]);
+ if (argv[i + 1])
+ bstr_xappend(NULL, &cmdline, bstr0(" "));
+ }
+
+ wchar_t *wcmdline = mp_from_utf8(ctx, cmdline.start);
+ talloc_free(cmdline.start);
+ return wcmdline;
+}
+
+static int create_overlapped_pipe(HANDLE *read, HANDLE *write)
+{
+ static atomic_ulong counter = ATOMIC_VAR_INIT(0);
+
+ // Generate pipe name
+ unsigned long id = atomic_fetch_add(&counter, 1);
+ unsigned pid = GetCurrentProcessId();
+ wchar_t buf[36];
+ swprintf(buf, sizeof(buf), L"\\\\?\\pipe\\mpv-anon-%08x-%08lx", pid, id);
+
+ // The function for creating anonymous pipes (CreatePipe) can't create
+ // overlapped pipes, so instead, use a named pipe with a unique name
+ *read = CreateNamedPipeW(buf, PIPE_ACCESS_INBOUND |
+ FILE_FLAG_FIRST_PIPE_INSTANCE | FILE_FLAG_OVERLAPPED,
+ PIPE_TYPE_BYTE | PIPE_WAIT | PIPE_REJECT_REMOTE_CLIENTS,
+ 1, 0, 4096, 0, NULL);
+ if (!*read)
+ goto error;
+
+ // Open the write end of the pipe as a synchronous handle
+ *write = CreateFileW(buf, GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
+ FILE_ATTRIBUTE_NORMAL, NULL);
+ if (*write == INVALID_HANDLE_VALUE)
+ goto error;
+
+ return 0;
+error:
+ *read = *write = INVALID_HANDLE_VALUE;
+ return -1;
+}
+
+static void delete_handle_list(void *p)
+{
+ LPPROC_THREAD_ATTRIBUTE_LIST list = p;
+ VOID (WINAPI *pDeleteProcThreadAttributeList)(LPPROC_THREAD_ATTRIBUTE_LIST);
+
+ HMODULE kernel32 = GetModuleHandleW(L"kernel32.dll");
+ pDeleteProcThreadAttributeList =
+ (VOID (WINAPI*)(LPPROC_THREAD_ATTRIBUTE_LIST))
+ GetProcAddress(kernel32, "DeleteProcThreadAttributeList");
+
+ if (pDeleteProcThreadAttributeList)
+ pDeleteProcThreadAttributeList(list);
+}
+
+// Create a PROC_THREAD_ATTRIBUTE_LIST that specifies exactly which handles are
+// inherited by the subprocess
+static LPPROC_THREAD_ATTRIBUTE_LIST create_handle_list(void *ctx,
+ HANDLE *handles, int num)
+{
+ WINBOOL (WINAPI *pInitializeProcThreadAttributeList)(
+ LPPROC_THREAD_ATTRIBUTE_LIST, DWORD, DWORD, PSIZE_T);
+ WINBOOL (WINAPI *pUpdateProcThreadAttribute)(LPPROC_THREAD_ATTRIBUTE_LIST,
+ DWORD, DWORD_PTR, PVOID, SIZE_T, PVOID, PSIZE_T);
+
+ // Load Windows Vista functions, if available
+ HMODULE kernel32 = GetModuleHandleW(L"kernel32.dll");
+ pInitializeProcThreadAttributeList =
+ (WINBOOL (WINAPI*)(LPPROC_THREAD_ATTRIBUTE_LIST, DWORD, DWORD, PSIZE_T))
+ GetProcAddress(kernel32, "InitializeProcThreadAttributeList");
+ pUpdateProcThreadAttribute =
+ (WINBOOL (WINAPI*)(LPPROC_THREAD_ATTRIBUTE_LIST, DWORD, DWORD_PTR,
+ PVOID, SIZE_T, PVOID, PSIZE_T))
+ GetProcAddress(kernel32, "UpdateProcThreadAttribute");
+ if (!pInitializeProcThreadAttributeList || !pUpdateProcThreadAttribute)
+ return NULL;
+
+ // Get required attribute list size
+ SIZE_T size = 0;
+ if (!pInitializeProcThreadAttributeList(NULL, 1, 0, &size)) {
+ if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+ return NULL;
+ }
+
+ // Allocate attribute list
+ LPPROC_THREAD_ATTRIBUTE_LIST list = talloc_size(ctx, size);
+ if (!pInitializeProcThreadAttributeList(list, 1, 0, &size))
+ goto error;
+ talloc_set_destructor(list, delete_handle_list);
+
+ if (!pUpdateProcThreadAttribute(list, 0, PROC_THREAD_ATTRIBUTE_HANDLE_LIST,
+ handles, num * sizeof(HANDLE), NULL, NULL))
+ goto error;
+
+ return list;
+error:
+ talloc_free(list);
+ return NULL;
+}
+
+// Helper method similar to sparse_poll, skips NULL handles
+static int sparse_wait(HANDLE *handles, unsigned num_handles)
+{
+ unsigned w_num_handles = 0;
+ HANDLE w_handles[num_handles];
+ int map[num_handles];
+
+ for (unsigned i = 0; i < num_handles; i++) {
+ if (!handles[i])
+ continue;
+
+ w_handles[w_num_handles] = handles[i];
+ map[w_num_handles] = i;
+ w_num_handles++;
+ }
+
+ if (w_num_handles == 0)
+ return -1;
+ DWORD i = WaitForMultipleObjects(w_num_handles, w_handles, FALSE, INFINITE);
+ i -= WAIT_OBJECT_0;
+
+ if (i >= w_num_handles)
+ return -1;
+ return map[i];
+}
+
+// Wrapper for ReadFile that treats ERROR_IO_PENDING as success
+static int async_read(HANDLE file, void *buf, unsigned size, OVERLAPPED* ol)
+{
+ if (!ReadFile(file, buf, size, NULL, ol))
+ return (GetLastError() == ERROR_IO_PENDING) ? 0 : -1;
+ return 0;
+}
+
+int mp_subprocess(char **args, struct mp_cancel *cancel, void *ctx,
+ subprocess_read_cb on_stdout, subprocess_read_cb on_stderr,
+ char **error)
+{
+ wchar_t *tmp = talloc_new(NULL);
+ int status = -1;
+ struct {
+ HANDLE read;
+ HANDLE write;
+ OVERLAPPED ol;
+ char buf[4096];
+ subprocess_read_cb read_cb;
+ } pipes[2] = {
+ { .read_cb = on_stdout },
+ { .read_cb = on_stderr },
+ };
+
+ // If the function exits before CreateProcess, there was an init error
+ *error = "init";
+
+ for (int i = 0; i < 2; i++) {
+ pipes[i].ol.hEvent = CreateEventW(NULL, TRUE, FALSE, NULL);
+ if (!pipes[i].ol.hEvent)
+ goto done;
+ if (create_overlapped_pipe(&pipes[i].read, &pipes[i].write))
+ goto done;
+ if (!SetHandleInformation(pipes[i].write, HANDLE_FLAG_INHERIT,
+ HANDLE_FLAG_INHERIT))
+ goto done;
+ }
+
+ // Convert the args array to a UTF-16 Windows command-line string
+ wchar_t *cmdline = write_cmdline(tmp, args);
+
+ DWORD flags = CREATE_UNICODE_ENVIRONMENT;
+ PROCESS_INFORMATION pi = {0};
+ STARTUPINFOEXW si = {
+ .StartupInfo = {
+ .cb = sizeof(si),
+ .dwFlags = STARTF_USESTDHANDLES,
+ .hStdInput = NULL,
+ .hStdOutput = pipes[0].write,
+ .hStdError = pipes[1].write,
+ },
+
+ // Specify which handles are inherited by the subprocess. If this isn't
+ // specified, the subprocess inherits all inheritable handles, which
+ // could include handles created by other threads. See:
+ // http://blogs.msdn.com/b/oldnewthing/archive/2011/12/16/10248328.aspx
+ .lpAttributeList = create_handle_list(tmp,
+ (HANDLE[]){ pipes[0].write, pipes[1].write }, 2),
+ };
+
+ // PROC_THREAD_ATTRIBUTE_LISTs are only supported in Vista and up. If not
+ // supported, create_handle_list will return NULL.
+ if (si.lpAttributeList)
+ flags |= EXTENDED_STARTUPINFO_PRESENT;
+
+ // If we have a console, the subprocess will automatically attach to it so
+ // it can receive Ctrl+C events. If we don't have a console, prevent the
+ // subprocess from creating its own console window by specifying
+ // CREATE_NO_WINDOW. GetConsoleCP() can be used to reliably determine if we
+ // have a console or not (Cygwin uses it too.)
+ if (!GetConsoleCP())
+ flags |= CREATE_NO_WINDOW;
+
+ if (!CreateProcessW(NULL, cmdline, NULL, NULL, TRUE, flags, NULL, NULL,
+ &si.StartupInfo, &pi))
+ goto done;
+ talloc_free(cmdline);
+ talloc_free(si.lpAttributeList);
+ CloseHandle(pi.hThread);
+
+ // Init is finished
+ *error = NULL;
+
+ // List of handles to watch with sparse_wait
+ HANDLE handles[] = { pipes[0].ol.hEvent, pipes[1].ol.hEvent, pi.hProcess,
+ cancel ? mp_cancel_get_event(cancel) : NULL };
+
+ for (int i = 0; i < 2; i++) {
+ // Close our copy of the write end of the pipes
+ CloseHandle(pipes[i].write);
+ pipes[i].write = NULL;
+
+ // Do the first read operation on each pipe
+ if (async_read(pipes[i].read, pipes[i].buf, 4096, &pipes[i].ol)) {
+ CloseHandle(pipes[i].read);
+ handles[i] = pipes[i].read = NULL;
+ }
+ }
+
+ DWORD r;
+ DWORD exit_code;
+ while (pipes[0].read || pipes[1].read || pi.hProcess) {
+ int i = sparse_wait(handles, MP_ARRAY_SIZE(handles));
+ switch (i) {
+ case 0:
+ case 1:
+ // Complete the read operation on the pipe
+ if (!GetOverlappedResult(pipes[i].read, &pipes[i].ol, &r, TRUE)) {
+ CloseHandle(pipes[i].read);
+ handles[i] = pipes[i].read = NULL;
+ break;
+ }
+
+ pipes[i].read_cb(ctx, pipes[i].buf, r);
+
+ // Begin the next read operation on the pipe
+ if (async_read(pipes[i].read, pipes[i].buf, 4096, &pipes[i].ol)) {
+ CloseHandle(pipes[i].read);
+ handles[i] = pipes[i].read = NULL;
+ }
+
+ break;
+ case 2:
+ GetExitCodeProcess(pi.hProcess, &exit_code);
+ status = exit_code;
+
+ CloseHandle(pi.hProcess);
+ handles[i] = pi.hProcess = NULL;
+ break;
+ case 3:
+ if (pi.hProcess) {
+ TerminateProcess(pi.hProcess, 1);
+ *error = "killed";
+ goto done;
+ }
+ break;
+ default:
+ goto done;
+ }
+ }
+
+done:
+ for (int i = 0; i < 2; i++) {
+ if (pipes[i].read) {
+ // Cancel any pending I/O (if the process was killed)
+ CancelIo(pipes[i].read);
+ GetOverlappedResult(pipes[i].read, &pipes[i].ol, &r, TRUE);
+ CloseHandle(pipes[i].read);
+ }
+ if (pipes[i].write) CloseHandle(pipes[i].write);
+ if (pipes[i].ol.hEvent) CloseHandle(pipes[i].ol.hEvent);
+ }
+ if (pi.hProcess) CloseHandle(pi.hProcess);
+ talloc_free(tmp);
+ return status;
+}
diff --git a/osdep/subprocess.h b/osdep/subprocess.h
new file mode 100644
index 0000000000..1ab4ddbdd7
--- /dev/null
+++ b/osdep/subprocess.h
@@ -0,0 +1,30 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with mpv. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef MP_SUBPROCESS_H_
+#define MP_SUBPROCESS_H_
+
+#include "stream/stream.h"
+
+typedef void (*subprocess_read_cb)(void *ctx, char *data, size_t size);
+
+// Start a subprocess. Uses callbacks to read from stdout and stderr.
+int mp_subprocess(char **args, struct mp_cancel *cancel, void *ctx,
+ subprocess_read_cb on_stdout, subprocess_read_cb on_stderr,
+ char **error);
+
+#endif