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-rw-r--r--compat/mingw.c184
1 files changed, 172 insertions, 12 deletions
diff --git a/compat/mingw.c b/compat/mingw.c
index 6ded1c859f..81ef24286a 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -5,6 +5,7 @@
#include "../strbuf.h"
#include "../run-command.h"
#include "../cache.h"
+#include "win32/lazyload.h"
#define HCAST(type, handle) ((type)(intptr_t)handle)
@@ -202,6 +203,31 @@ static int ask_yes_no_if_possible(const char *format, ...)
}
}
+/* Normalizes NT paths as returned by some low-level APIs. */
+static wchar_t *normalize_ntpath(wchar_t *wbuf)
+{
+ int i;
+ /* fix absolute path prefixes */
+ if (wbuf[0] == '\\') {
+ /* strip NT namespace prefixes */
+ if (!wcsncmp(wbuf, L"\\??\\", 4) ||
+ !wcsncmp(wbuf, L"\\\\?\\", 4))
+ wbuf += 4;
+ else if (!wcsnicmp(wbuf, L"\\DosDevices\\", 12))
+ wbuf += 12;
+ /* replace remaining '...UNC\' with '\\' */
+ if (!wcsnicmp(wbuf, L"UNC\\", 4)) {
+ wbuf += 2;
+ *wbuf = '\\';
+ }
+ }
+ /* convert backslashes to slashes */
+ for (i = 0; wbuf[i]; i++)
+ if (wbuf[i] == '\\')
+ wbuf[i] = '/';
+ return wbuf;
+}
+
int mingw_unlink(const char *pathname)
{
int ret, tries = 0;
@@ -341,12 +367,74 @@ int mingw_mkdir(const char *path, int mode)
return ret;
}
+/*
+ * Calling CreateFile() using FILE_APPEND_DATA and without FILE_WRITE_DATA
+ * is documented in [1] as opening a writable file handle in append mode.
+ * (It is believed that) this is atomic since it is maintained by the
+ * kernel unlike the O_APPEND flag which is racily maintained by the CRT.
+ *
+ * [1] https://docs.microsoft.com/en-us/windows/desktop/fileio/file-access-rights-constants
+ *
+ * This trick does not appear to work for named pipes. Instead it creates
+ * a named pipe client handle that cannot be written to. Callers should
+ * just use the regular _wopen() for them. (And since client handle gets
+ * bound to a unique server handle, it isn't really an issue.)
+ */
+static int mingw_open_append(wchar_t const *wfilename, int oflags, ...)
+{
+ HANDLE handle;
+ int fd;
+ DWORD create = (oflags & O_CREAT) ? OPEN_ALWAYS : OPEN_EXISTING;
+
+ /* only these flags are supported */
+ if ((oflags & ~O_CREAT) != (O_WRONLY | O_APPEND))
+ return errno = ENOSYS, -1;
+
+ /*
+ * FILE_SHARE_WRITE is required to permit child processes
+ * to append to the file.
+ */
+ handle = CreateFileW(wfilename, FILE_APPEND_DATA,
+ FILE_SHARE_WRITE | FILE_SHARE_READ,
+ NULL, create, FILE_ATTRIBUTE_NORMAL, NULL);
+ if (handle == INVALID_HANDLE_VALUE)
+ return errno = err_win_to_posix(GetLastError()), -1;
+
+ /*
+ * No O_APPEND here, because the CRT uses it only to reset the
+ * file pointer to EOF before each write(); but that is not
+ * necessary (and may lead to races) for a file created with
+ * FILE_APPEND_DATA.
+ */
+ fd = _open_osfhandle((intptr_t)handle, O_BINARY);
+ if (fd < 0)
+ CloseHandle(handle);
+ return fd;
+}
+
+/*
+ * Does the pathname map to the local named pipe filesystem?
+ * That is, does it have a "//./pipe/" prefix?
+ */
+static int is_local_named_pipe_path(const char *filename)
+{
+ return (is_dir_sep(filename[0]) &&
+ is_dir_sep(filename[1]) &&
+ filename[2] == '.' &&
+ is_dir_sep(filename[3]) &&
+ !strncasecmp(filename+4, "pipe", 4) &&
+ is_dir_sep(filename[8]) &&
+ filename[9]);
+}
+
int mingw_open (const char *filename, int oflags, ...)
{
+ typedef int (*open_fn_t)(wchar_t const *wfilename, int oflags, ...);
va_list args;
unsigned mode;
int fd;
wchar_t wfilename[MAX_PATH];
+ open_fn_t open_fn;
va_start(args, oflags);
mode = va_arg(args, int);
@@ -355,9 +443,14 @@ int mingw_open (const char *filename, int oflags, ...)
if (filename && !strcmp(filename, "/dev/null"))
filename = "nul";
+ if ((oflags & O_APPEND) && !is_local_named_pipe_path(filename))
+ open_fn = mingw_open_append;
+ else
+ open_fn = _wopen;
+
if (xutftowcs_path(wfilename, filename) < 0)
return -1;
- fd = _wopen(wfilename, oflags, mode);
+ fd = open_fn(wfilename, oflags, mode);
if (fd < 0 && (oflags & O_ACCMODE) != O_RDONLY && errno == EACCES) {
DWORD attrs = GetFileAttributesW(wfilename);
@@ -375,7 +468,7 @@ int mingw_open (const char *filename, int oflags, ...)
* CREATE_ALWAYS flag of CreateFile()).
*/
if (fd < 0 && errno == EACCES)
- fd = _wopen(wfilename, oflags & ~O_CREAT, mode);
+ fd = open_fn(wfilename, oflags & ~O_CREAT, mode);
if (fd >= 0 && set_hidden_flag(wfilename, 1))
warning("could not mark '%s' as hidden.", filename);
}
@@ -850,8 +943,29 @@ struct tm *localtime_r(const time_t *timep, struct tm *result)
char *mingw_getcwd(char *pointer, int len)
{
- wchar_t wpointer[MAX_PATH];
- if (!_wgetcwd(wpointer, ARRAY_SIZE(wpointer)))
+ wchar_t cwd[MAX_PATH], wpointer[MAX_PATH];
+ DWORD ret = GetCurrentDirectoryW(ARRAY_SIZE(cwd), cwd);
+
+ if (!ret || ret >= ARRAY_SIZE(cwd)) {
+ errno = ret ? ENAMETOOLONG : err_win_to_posix(GetLastError());
+ return NULL;
+ }
+ ret = GetLongPathNameW(cwd, wpointer, ARRAY_SIZE(wpointer));
+ if (!ret && GetLastError() == ERROR_ACCESS_DENIED) {
+ HANDLE hnd = CreateFileW(cwd, 0,
+ FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+ OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+ if (hnd == INVALID_HANDLE_VALUE)
+ return NULL;
+ ret = GetFinalPathNameByHandleW(hnd, wpointer, ARRAY_SIZE(wpointer), 0);
+ CloseHandle(hnd);
+ if (!ret || ret >= ARRAY_SIZE(wpointer))
+ return NULL;
+ if (xwcstoutf(pointer, normalize_ntpath(wpointer), len) < 0)
+ return NULL;
+ return pointer;
+ }
+ if (!ret || ret >= ARRAY_SIZE(wpointer))
return NULL;
if (xwcstoutf(pointer, wpointer, len) < 0)
return NULL;
@@ -1510,7 +1624,8 @@ static void ensure_socket_initialization(void)
WSAGetLastError());
for (name = libraries; *name; name++) {
- ipv6_dll = LoadLibrary(*name);
+ ipv6_dll = LoadLibraryExA(*name, NULL,
+ LOAD_LIBRARY_SEARCH_SYSTEM32);
if (!ipv6_dll)
continue;
@@ -1731,18 +1846,63 @@ int mingw_getpagesize(void)
return si.dwAllocationGranularity;
}
+/* See https://msdn.microsoft.com/en-us/library/windows/desktop/ms724435.aspx */
+enum EXTENDED_NAME_FORMAT {
+ NameDisplay = 3,
+ NameUserPrincipal = 8
+};
+
+static char *get_extended_user_info(enum EXTENDED_NAME_FORMAT type)
+{
+ DECLARE_PROC_ADDR(secur32.dll, BOOL, GetUserNameExW,
+ enum EXTENDED_NAME_FORMAT, LPCWSTR, PULONG);
+ static wchar_t wbuffer[1024];
+ DWORD len;
+
+ if (!INIT_PROC_ADDR(GetUserNameExW))
+ return NULL;
+
+ len = ARRAY_SIZE(wbuffer);
+ if (GetUserNameExW(type, wbuffer, &len)) {
+ char *converted = xmalloc((len *= 3));
+ if (xwcstoutf(converted, wbuffer, len) >= 0)
+ return converted;
+ free(converted);
+ }
+
+ return NULL;
+}
+
+char *mingw_query_user_email(void)
+{
+ return get_extended_user_info(NameUserPrincipal);
+}
+
struct passwd *getpwuid(int uid)
{
+ static unsigned initialized;
static char user_name[100];
- static struct passwd p;
+ static struct passwd *p;
+ DWORD len;
- DWORD len = sizeof(user_name);
- if (!GetUserName(user_name, &len))
+ if (initialized)
+ return p;
+
+ len = sizeof(user_name);
+ if (!GetUserName(user_name, &len)) {
+ initialized = 1;
return NULL;
- p.pw_name = user_name;
- p.pw_gecos = "unknown";
- p.pw_dir = NULL;
- return &p;
+ }
+
+ p = xmalloc(sizeof(*p));
+ p->pw_name = user_name;
+ p->pw_gecos = get_extended_user_info(NameDisplay);
+ if (!p->pw_gecos)
+ p->pw_gecos = "unknown";
+ p->pw_dir = NULL;
+
+ initialized = 1;
+ return p;
}
static HANDLE timer_event;