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-rw-r--r--lib/windows-spawn.c727
1 files changed, 727 insertions, 0 deletions
diff --git a/lib/windows-spawn.c b/lib/windows-spawn.c
new file mode 100644
index 0000000..a9212d4
--- /dev/null
+++ b/lib/windows-spawn.c
@@ -0,0 +1,727 @@
+/* Auxiliary functions for the creation of subprocesses. Native Windows API.
+ Copyright (C) 2001, 2003-2022 Free Software Foundation, Inc.
+ Written by Bruno Haible <bruno@clisp.org>, 2003.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file 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 Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include "windows-spawn.h"
+
+/* Get declarations of the native Windows API functions. */
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+/* Get _get_osfhandle(). */
+#if GNULIB_MSVC_NOTHROW
+# include "msvc-nothrow.h"
+#else
+# include <io.h>
+#endif
+#include <process.h>
+
+#include "findprog.h"
+
+/* Don't assume that UNICODE is not defined. */
+#undef STARTUPINFO
+#define STARTUPINFO STARTUPINFOA
+#undef CreateProcess
+#define CreateProcess CreateProcessA
+
+#define SHELL_SPECIAL_CHARS "\"\\ \001\002\003\004\005\006\007\010\011\012\013\014\015\016\017\020\021\022\023\024\025\026\027\030\031\032\033\034\035\036\037*?"
+#define SHELL_SPACE_CHARS " \001\002\003\004\005\006\007\010\011\012\013\014\015\016\017\020\021\022\023\024\025\026\027\030\031\032\033\034\035\036\037"
+
+/* Returns the length of a quoted argument string. */
+static size_t
+quoted_arg_length (const char *string)
+{
+ bool quote_around = (strpbrk (string, SHELL_SPACE_CHARS) != NULL);
+ size_t length;
+ unsigned int backslashes;
+ const char *s;
+
+ length = 0;
+ backslashes = 0;
+ if (quote_around)
+ length++;
+ for (s = string; *s != '\0'; s++)
+ {
+ char c = *s;
+ if (c == '"')
+ length += backslashes + 1;
+ length++;
+ if (c == '\\')
+ backslashes++;
+ else
+ backslashes = 0;
+ }
+ if (quote_around)
+ length += backslashes + 1;
+
+ return length;
+}
+
+/* Produces a quoted argument string.
+ Stores exactly quoted_arg_length (STRING) + 1 bytes, including the final
+ NUL byte, at MEM.
+ Returns a pointer past the stored quoted argument string. */
+static char *
+quoted_arg_string (const char *string, char *mem)
+{
+ bool quote_around = (strpbrk (string, SHELL_SPACE_CHARS) != NULL);
+ char *p;
+ unsigned int backslashes;
+ const char *s;
+
+ p = mem;
+ backslashes = 0;
+ if (quote_around)
+ *p++ = '"';
+ for (s = string; *s != '\0'; s++)
+ {
+ char c = *s;
+ if (c == '"')
+ {
+ unsigned int j;
+ for (j = backslashes + 1; j > 0; j--)
+ *p++ = '\\';
+ }
+ *p++ = c;
+ if (c == '\\')
+ backslashes++;
+ else
+ backslashes = 0;
+ }
+ if (quote_around)
+ {
+ unsigned int j;
+ for (j = backslashes; j > 0; j--)
+ *p++ = '\\';
+ *p++ = '"';
+ }
+ *p++ = '\0';
+
+ return p;
+}
+
+const char **
+prepare_spawn (const char * const *argv, char **mem_to_free)
+{
+ size_t argc;
+ const char **new_argv;
+ size_t i;
+
+ /* Count number of arguments. */
+ for (argc = 0; argv[argc] != NULL; argc++)
+ ;
+
+ /* Allocate new argument vector. */
+ new_argv = (const char **) malloc ((1 + argc + 1) * sizeof (const char *));
+
+ /* Add an element upfront that can be used when argv[0] turns out to be a
+ script, not a program.
+ On Unix, this would be "/bin/sh". On native Windows, "sh" is actually
+ "sh.exe". We have to omit the directory part and rely on the search in
+ PATH, because the mingw "mount points" are not visible inside Windows
+ CreateProcess(). */
+ new_argv[0] = "sh.exe";
+
+ /* Put quoted arguments into the new argument vector. */
+ size_t needed_size = 0;
+ for (i = 0; i < argc; i++)
+ {
+ const char *string = argv[i];
+ size_t length;
+
+ if (string[0] == '\0')
+ length = strlen ("\"\"");
+ else if (strpbrk (string, SHELL_SPECIAL_CHARS) != NULL)
+ length = quoted_arg_length (string);
+ else
+ length = strlen (string);
+ needed_size += length + 1;
+ }
+
+ char *mem;
+ if (needed_size == 0)
+ mem = NULL;
+ else
+ {
+ mem = (char *) malloc (needed_size);
+ if (mem == NULL)
+ {
+ /* Memory allocation failure. */
+ free (new_argv);
+ errno = ENOMEM;
+ return NULL;
+ }
+ }
+ *mem_to_free = mem;
+
+ for (i = 0; i < argc; i++)
+ {
+ const char *string = argv[i];
+
+ new_argv[1 + i] = mem;
+ if (string[0] == '\0')
+ {
+ size_t length = strlen ("\"\"");
+ memcpy (mem, "\"\"", length + 1);
+ mem += length + 1;
+ }
+ else if (strpbrk (string, SHELL_SPECIAL_CHARS) != NULL)
+ {
+ mem = quoted_arg_string (string, mem);
+ }
+ else
+ {
+ size_t length = strlen (string);
+ memcpy (mem, string, length + 1);
+ mem += length + 1;
+ }
+ }
+ new_argv[1 + argc] = NULL;
+
+ return new_argv;
+}
+
+char *
+compose_command (const char * const *argv)
+{
+ /* Just concatenate the argv[] strings, separated by spaces. */
+ char *command;
+
+ /* Determine the size of the needed block of memory. */
+ size_t total_size = 0;
+ const char * const *ap;
+ const char *p;
+ for (ap = argv; (p = *ap) != NULL; ap++)
+ total_size += strlen (p) + 1;
+ size_t command_size = (total_size > 0 ? total_size : 1);
+
+ /* Allocate the block of memory. */
+ command = (char *) malloc (command_size);
+ if (command == NULL)
+ {
+ errno = ENOMEM;
+ return NULL;
+ }
+
+ /* Fill it. */
+ if (total_size > 0)
+ {
+ char *cp = command;
+ for (ap = argv; (p = *ap) != NULL; ap++)
+ {
+ size_t size = strlen (p) + 1;
+ memcpy (cp, p, size - 1);
+ cp += size;
+ cp[-1] = ' ';
+ }
+ cp[-1] = '\0';
+ }
+ else
+ *command = '\0';
+
+ return command;
+}
+
+char *
+compose_envblock (const char * const *envp)
+{
+ /* This is a bit hairy, because we don't have a lock that would prevent other
+ threads from making modifications in ENVP. So, just make sure we don't
+ crash; but if other threads are making modifications, part of the result
+ may be wrong. */
+ retry:
+ {
+ /* Guess the size of the needed block of memory.
+ The guess will be exact if other threads don't make modifications. */
+ size_t total_size = 0;
+ const char * const *ep;
+ const char *p;
+ for (ep = envp; (p = *ep) != NULL; ep++)
+ total_size += strlen (p) + 1;
+ size_t envblock_size = total_size;
+
+ /* Allocate the block of memory. */
+ char *envblock = (char *) malloc (envblock_size + 1);
+ if (envblock == NULL)
+ {
+ errno = ENOMEM;
+ return NULL;
+ }
+ size_t envblock_used = 0;
+ for (ep = envp; (p = *ep) != NULL; ep++)
+ {
+ size_t size = strlen (p) + 1;
+ if (envblock_used + size > envblock_size)
+ {
+ /* Other threads did modifications. Need more memory. */
+ envblock_size += envblock_size / 2;
+ if (envblock_used + size > envblock_size)
+ envblock_size = envblock_used + size;
+
+ char *new_envblock = (char *) realloc (envblock, envblock_size + 1);
+ if (new_envblock == NULL)
+ {
+ free (envblock);
+ errno = ENOMEM;
+ return NULL;
+ }
+ envblock = new_envblock;
+ }
+ memcpy (envblock + envblock_used, p, size);
+ envblock_used += size;
+ if (envblock[envblock_used - 1] != '\0')
+ {
+ /* Other threads did modifications. Restart. */
+ free (envblock);
+ goto retry;
+ }
+ }
+ envblock[envblock_used] = '\0';
+ return envblock;
+ }
+}
+
+int
+init_inheritable_handles (struct inheritable_handles *inh_handles,
+ bool duplicate)
+{
+ /* Determine the minimal count of handles we need to care about. */
+ size_t handles_count;
+ {
+ /* _getmaxstdio
+ <https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/getmaxstdio>
+ Default value is 512. */
+ unsigned int fdmax = _getmaxstdio ();
+ if (fdmax < 3)
+ fdmax = 3;
+ for (; fdmax > 3; fdmax--)
+ {
+ unsigned int fd = fdmax - 1;
+ /* _get_osfhandle
+ <https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle> */
+ HANDLE handle = (HANDLE) _get_osfhandle (fd);
+ if (handle != INVALID_HANDLE_VALUE)
+ {
+ DWORD hflags;
+ /* GetHandleInformation
+ <https://docs.microsoft.com/en-us/windows/win32/api/handleapi/nf-handleapi-gethandleinformation> */
+ if (GetHandleInformation (handle, &hflags))
+ {
+ if ((hflags & HANDLE_FLAG_INHERIT) != 0)
+ /* fd denotes an inheritable descriptor. */
+ break;
+ }
+ }
+ }
+ handles_count = fdmax;
+ }
+ /* Note: handles_count >= 3. */
+
+ /* Allocate the arrays. */
+ size_t handles_allocated = handles_count;
+ HANDLE *handles_array =
+ (HANDLE *) malloc (handles_allocated * sizeof (HANDLE));
+ if (handles_array == NULL)
+ {
+ errno = ENOMEM;
+ return -1;
+ }
+ unsigned char *flags_array =
+ (unsigned char *) malloc (handles_allocated * sizeof (unsigned char));
+ if (flags_array == NULL)
+ {
+ free (handles_array);
+ errno = ENOMEM;
+ return -1;
+ }
+
+ /* Fill in the two arrays. */
+ {
+ HANDLE curr_process = (duplicate ? GetCurrentProcess () : INVALID_HANDLE_VALUE);
+ unsigned int fd;
+ for (fd = 0; fd < handles_count; fd++)
+ {
+ handles_array[fd] = INVALID_HANDLE_VALUE;
+ /* _get_osfhandle
+ <https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/get-osfhandle> */
+ HANDLE handle = (HANDLE) _get_osfhandle (fd);
+ if (handle != INVALID_HANDLE_VALUE)
+ {
+ DWORD hflags;
+ /* GetHandleInformation
+ <https://docs.microsoft.com/en-us/windows/win32/api/handleapi/nf-handleapi-gethandleinformation> */
+ if (GetHandleInformation (handle, &hflags))
+ {
+ if ((hflags & HANDLE_FLAG_INHERIT) != 0)
+ {
+ /* fd denotes an inheritable descriptor. */
+ if (duplicate)
+ {
+ if (!DuplicateHandle (curr_process, handle,
+ curr_process, &handles_array[fd],
+ 0, TRUE, DUPLICATE_SAME_ACCESS))
+ {
+ unsigned int i;
+ for (i = 0; i < fd; i++)
+ if (handles_array[i] != INVALID_HANDLE_VALUE)
+ CloseHandle (handles_array[i]);
+ free (flags_array);
+ free (handles_array);
+ errno = EBADF; /* arbitrary */
+ return -1;
+ }
+ }
+ else
+ handles_array[fd] = handle;
+
+ flags_array[fd] = 0;
+ }
+ }
+ }
+ }
+ }
+
+ /* Return the result. */
+ inh_handles->count = handles_count;
+ inh_handles->allocated = handles_allocated;
+ inh_handles->handles = handles_array;
+ inh_handles->flags = flags_array;
+ return 0;
+}
+
+int
+compose_handles_block (const struct inheritable_handles *inh_handles,
+ STARTUPINFO *sinfo)
+{
+ /* STARTUPINFO
+ <https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/ns-processthreadsapi-startupinfoa> */
+ sinfo->dwFlags = STARTF_USESTDHANDLES;
+ sinfo->hStdInput = inh_handles->handles[0];
+ sinfo->hStdOutput = inh_handles->handles[1];
+ sinfo->hStdError = inh_handles->handles[2];
+
+ /* On newer versions of Windows, more file descriptors / handles than the
+ first three can be passed.
+ The format is as follows: Let N be an exclusive upper bound for the file
+ descriptors to be passed. Two arrays are constructed in memory:
+ - flags[0..N-1], of element type 'unsigned char',
+ - handles[0..N-1], of element type 'HANDLE' or 'intptr_t'.
+ For used entries, handles[i] is the handle, and flags[i] is a set of flags,
+ a combination of:
+ 1 for open file descriptors,
+ 64 for handles of type FILE_TYPE_CHAR,
+ 8 for handles of type FILE_TYPE_PIPE,
+ 32 for O_APPEND.
+ For unused entries - this may include any of the first three, since they
+ are already passed above -, handles[i] is INVALID_HANDLE_VALUE and flags[i]
+ is zero.
+ lpReserved2 now is a pointer to the concatenation (without padding) of:
+ - an 'unsigned int' whose value is N,
+ - the contents of the flags[0..N-1] array,
+ - the contents of the handles[0..N-1] array.
+ cbReserved2 is the size (in bytes) of the object at lpReserved2. */
+
+ size_t handles_count = inh_handles->count;
+
+ sinfo->cbReserved2 =
+ sizeof (unsigned int)
+ + handles_count * sizeof (unsigned char)
+ + handles_count * sizeof (HANDLE);
+ /* Add some padding, so that we can work with a properly aligned HANDLE
+ array. */
+ char *hblock = (char *) malloc (sinfo->cbReserved2 + (sizeof (HANDLE) - 1));
+ if (hblock == NULL)
+ {
+ errno = ENOMEM;
+ return -1;
+ }
+ unsigned char *flags = (unsigned char *) (hblock + sizeof (unsigned int));
+ char *handles = (char *) (flags + handles_count);
+ HANDLE *handles_aligned =
+ (HANDLE *) (((uintptr_t) handles + (sizeof (HANDLE) - 1))
+ & - (uintptr_t) sizeof (HANDLE));
+
+ * (unsigned int *) hblock = handles_count;
+ {
+ unsigned int fd;
+ for (fd = 0; fd < handles_count; fd++)
+ {
+ handles_aligned[fd] = INVALID_HANDLE_VALUE;
+ flags[fd] = 0;
+
+ HANDLE handle = inh_handles->handles[fd];
+ if (handle != INVALID_HANDLE_VALUE
+ /* The first three are possibly already passed above.
+ But they need to passed here as well, if they have some flags. */
+ && (fd >= 3 || inh_handles->flags[fd] != 0))
+ {
+ DWORD hflags;
+ /* GetHandleInformation
+ <https://docs.microsoft.com/en-us/windows/win32/api/handleapi/nf-handleapi-gethandleinformation> */
+ if (GetHandleInformation (handle, &hflags))
+ {
+ if ((hflags & HANDLE_FLAG_INHERIT) != 0)
+ {
+ /* fd denotes an inheritable descriptor. */
+ handles_aligned[fd] = handle;
+ /* On Microsoft Windows, it would be sufficient to set
+ flags[fd] = 1. But on ReactOS or Wine, adding the bit
+ that indicates the handle type may be necessary. So,
+ just do it everywhere. */
+ flags[fd] = 1 | inh_handles->flags[fd];
+ switch (GetFileType (handle))
+ {
+ case FILE_TYPE_CHAR:
+ flags[fd] |= 64;
+ break;
+ case FILE_TYPE_PIPE:
+ flags[fd] |= 8;
+ break;
+ default:
+ break;
+ }
+ }
+ else
+ /* We shouldn't have any non-inheritable handles in
+ inh_handles->handles. */
+ abort ();
+ }
+ }
+ }
+ }
+ if (handles != (char *) handles_aligned)
+ memmove (handles, (char *) handles_aligned, handles_count * sizeof (HANDLE));
+
+ sinfo->lpReserved2 = (BYTE *) hblock;
+
+ return 0;
+}
+
+void
+free_inheritable_handles (struct inheritable_handles *inh_handles)
+{
+ free (inh_handles->flags);
+ free (inh_handles->handles);
+}
+
+int
+convert_CreateProcess_error (DWORD error)
+{
+ /* Some of these errors probably cannot happen. But who knows... */
+ switch (error)
+ {
+ case ERROR_FILE_NOT_FOUND:
+ case ERROR_PATH_NOT_FOUND:
+ case ERROR_BAD_PATHNAME:
+ case ERROR_BAD_NET_NAME:
+ case ERROR_INVALID_NAME:
+ case ERROR_DIRECTORY:
+ return ENOENT;
+ break;
+
+ case ERROR_ACCESS_DENIED:
+ case ERROR_SHARING_VIOLATION:
+ return EACCES;
+ break;
+
+ case ERROR_OUTOFMEMORY:
+ return ENOMEM;
+ break;
+
+ case ERROR_BUFFER_OVERFLOW:
+ case ERROR_FILENAME_EXCED_RANGE:
+ return ENAMETOOLONG;
+ break;
+
+ case ERROR_BAD_FORMAT:
+ case ERROR_BAD_EXE_FORMAT:
+ return ENOEXEC;
+ break;
+
+ default:
+ return EINVAL;
+ break;
+ }
+}
+
+intptr_t
+spawnpvech (int mode,
+ const char *progname, const char * const *argv,
+ const char * const *envp,
+ const char *currdir,
+ HANDLE stdin_handle, HANDLE stdout_handle, HANDLE stderr_handle)
+{
+ /* Validate the arguments. */
+ if (!(mode == P_WAIT
+ || mode == P_NOWAIT
+ || mode == P_DETACH
+ || mode == P_OVERLAY)
+ || progname == NULL || argv == NULL)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ /* Implement the 'p' letter: search for PROGNAME in getenv ("PATH"). */
+ const char *resolved_progname =
+ find_in_given_path (progname, getenv ("PATH"), NULL, false);
+ if (resolved_progname == NULL)
+ return -1;
+
+ /* Compose the command. */
+ char *command = compose_command (argv);
+ if (command == NULL)
+ goto out_of_memory_1;
+
+ /* Copy *ENVP into a contiguous block of memory. */
+ char *envblock;
+ if (envp == NULL)
+ envblock = NULL;
+ else
+ {
+ envblock = compose_envblock (envp);
+ if (envblock == NULL)
+ goto out_of_memory_2;
+ }
+
+ /* Collect the inheritable handles. */
+ struct inheritable_handles inh_handles;
+ if (init_inheritable_handles (&inh_handles, false) < 0)
+ {
+ int saved_errno = errno;
+ if (envblock != NULL)
+ free (envblock);
+ free (command);
+ if (resolved_progname != progname)
+ free ((char *) resolved_progname);
+ errno = saved_errno;
+ return -1;
+ }
+ inh_handles.handles[0] = stdin_handle; inh_handles.flags[0] = 0;
+ inh_handles.handles[1] = stdout_handle; inh_handles.flags[1] = 0;
+ inh_handles.handles[2] = stderr_handle; inh_handles.flags[2] = 0;
+
+ /* CreateProcess
+ <https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-createprocessa> */
+ /* <https://docs.microsoft.com/en-us/windows/win32/procthread/process-creation-flags> */
+ DWORD process_creation_flags = (mode == P_DETACH ? DETACHED_PROCESS : 0);
+ /* STARTUPINFO
+ <https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/ns-processthreadsapi-startupinfoa> */
+ STARTUPINFO sinfo;
+ sinfo.cb = sizeof (STARTUPINFO);
+ sinfo.lpReserved = NULL;
+ sinfo.lpDesktop = NULL;
+ sinfo.lpTitle = NULL;
+ if (compose_handles_block (&inh_handles, &sinfo) < 0)
+ {
+ int saved_errno = errno;
+ free_inheritable_handles (&inh_handles);
+ if (envblock != NULL)
+ free (envblock);
+ free (command);
+ if (resolved_progname != progname)
+ free ((char *) resolved_progname);
+ errno = saved_errno;
+ return -1;
+ }
+
+ PROCESS_INFORMATION pinfo;
+ if (!CreateProcess (resolved_progname, command, NULL, NULL, TRUE,
+ process_creation_flags, envblock, currdir, &sinfo,
+ &pinfo))
+ {
+ DWORD error = GetLastError ();
+
+ free (sinfo.lpReserved2);
+ free_inheritable_handles (&inh_handles);
+ if (envblock != NULL)
+ free (envblock);
+ free (command);
+ if (resolved_progname != progname)
+ free ((char *) resolved_progname);
+
+ errno = convert_CreateProcess_error (error);
+ return -1;
+ }
+
+ if (pinfo.hThread)
+ CloseHandle (pinfo.hThread);
+ free (sinfo.lpReserved2);
+ free_inheritable_handles (&inh_handles);
+ if (envblock != NULL)
+ free (envblock);
+ free (command);
+ if (resolved_progname != progname)
+ free ((char *) resolved_progname);
+
+ switch (mode)
+ {
+ case P_WAIT:
+ {
+ /* Wait until it terminates. Then get its exit status code. */
+ switch (WaitForSingleObject (pinfo.hProcess, INFINITE))
+ {
+ case WAIT_OBJECT_0:
+ break;
+ case WAIT_FAILED:
+ errno = ECHILD;
+ return -1;
+ default:
+ abort ();
+ }
+
+ DWORD exit_code;
+ if (!GetExitCodeProcess (pinfo.hProcess, &exit_code))
+ {
+ errno = ECHILD;
+ return -1;
+ }
+ CloseHandle (pinfo.hProcess);
+ return exit_code;
+ }
+
+ case P_NOWAIT:
+ /* Return pinfo.hProcess, not pinfo.dwProcessId. */
+ return (intptr_t) pinfo.hProcess;
+
+ case P_DETACH:
+ case P_OVERLAY:
+ CloseHandle (pinfo.hProcess);
+ return 0;
+
+ default:
+ /* Already checked above. */
+ abort ();
+ }
+
+ /*NOTREACHED*/
+ out_of_memory_2:
+ free (command);
+ out_of_memory_1:
+ if (resolved_progname != progname)
+ free ((char *) resolved_progname);
+ errno = ENOMEM;
+ return -1;
+}