src/win32/findfile.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #include "findfile.h"
   9
  10 #include "path_w32.h"
  11 #include "utf-conv.h"
  12 #include "path.h"
  13
  14 #define REG_MSYSGIT_INSTALL_LOCAL L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\Git_is1"
  15
  16 #ifndef _WIN64
  17 #define REG_MSYSGIT_INSTALL REG_MSYSGIT_INSTALL_LOCAL
  18 #else
  19 #define REG_MSYSGIT_INSTALL L"SOFTWARE\\Wow6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\Git_is1"
  20 #endif
  21
  22 typedef struct {
  23         git_win32_path path;
  24         DWORD len;
  25 } _findfile_path;
  26
  27 static int git_win32__expand_path(_findfile_path *dest, const wchar_t *src)
  28 {
  29         dest->len = ExpandEnvironmentStringsW(src, dest->path, ARRAY_SIZE(dest->path));
  30
  31         if (!dest->len || dest->len > ARRAY_SIZE(dest->path))
  32                 return -1;
  33
  34         return 0;
  35 }
  36
  37 static int win32_path_to_8(git_buf *dest, const wchar_t *src)
  38 {
  39         git_win32_utf8_path utf8_path;
  40
  41         if (git_win32_path_to_utf8(utf8_path, src) < 0) {
  42                 git_error_set(GIT_ERROR_OS, "unable to convert path to UTF-8");
  43                 return -1;
  44         }
  45
  46         /* Convert backslashes to forward slashes */
  47         git_path_mkposix(utf8_path);
  48
  49         return git_buf_sets(dest, utf8_path);
  50 }
  51
  52 static wchar_t *win32_walkpath(wchar_t *path, wchar_t *buf, size_t buflen)
  53 {
  54         wchar_t term, *base = path;
  55
  56         GIT_ASSERT_ARG_WITH_RETVAL(path, NULL);
  57         GIT_ASSERT_ARG_WITH_RETVAL(buf, NULL);
  58         GIT_ASSERT_ARG_WITH_RETVAL(buflen, NULL);
  59
  60         term = (*path == L'"') ? *path++ : L';';
  61
  62         for (buflen--; *path && *path != term && buflen; buflen--)
  63                 *buf++ = *path++;
  64
  65         *buf = L'\0'; /* reserved a byte via initial subtract */
  66
  67         while (*path == term || *path == L';')
  68                 path++;
  69
  70         return (path != base) ? path : NULL;
  71 }
  72
  73 static int win32_find_git_in_path(git_buf *buf, const wchar_t *gitexe, const wchar_t *subdir)
  74 {
  75         wchar_t *env = _wgetenv(L"PATH"), lastch;
  76         _findfile_path root;
  77         size_t gitexe_len = wcslen(gitexe);
  78
  79         if (!env)
  80                 return -1;
  81
  82         while ((env = win32_walkpath(env, root.path, MAX_PATH-1)) && *root.path) {
  83                 root.len = (DWORD)wcslen(root.path);
  84                 lastch = root.path[root.len - 1];
  85
  86                 /* ensure trailing slash (MAX_PATH-1 to walkpath guarantees space) */
  87                 if (lastch != L'/' && lastch != L'\\') {
  88                         root.path[root.len++] = L'\\';
  89                         root.path[root.len]   = L'\0';
  90                 }
  91
  92                 if (root.len + gitexe_len >= MAX_PATH)
  93                         continue;
  94                 wcscpy(&root.path[root.len], gitexe);
  95
  96                 if (_waccess(root.path, F_OK) == 0 && root.len > 5) {
  97                         /* replace "bin\\" or "cmd\\" with subdir */
  98                         wcscpy(&root.path[root.len - 4], subdir);
  99
 100                         win32_path_to_8(buf, root.path);
 101                         return 0;
 102                 }
 103         }
 104
 105         return GIT_ENOTFOUND;
 106 }
 107
 108 static int win32_find_git_in_registry(
 109         git_buf *buf, const HKEY hive, const wchar_t *key, const wchar_t *subdir)
 110 {
 111         HKEY hKey;
 112         int error = GIT_ENOTFOUND;
 113
 114         GIT_ASSERT_ARG(buf);
 115
 116         if (!RegOpenKeyExW(hive, key, 0, KEY_READ, &hKey)) {
 117                 DWORD dwType, cbData;
 118                 git_win32_path path;
 119
 120                 /* Ensure that the buffer is big enough to have the suffix attached
 121                  * after we receive the result. */
 122                 cbData = (DWORD)(sizeof(path) - wcslen(subdir) * sizeof(wchar_t));
 123
 124                 /* InstallLocation points to the root of the git directory */
 125                 if (!RegQueryValueExW(hKey, L"InstallLocation", NULL, &dwType, (LPBYTE)path, &cbData) &&
 126                         dwType == REG_SZ) {
 127
 128                         /* Append the suffix */
 129                         wcscat(path, subdir);
 130
 131                         /* Convert to UTF-8, with forward slashes, and output the path
 132                          * to the provided buffer */
 133                         if (!win32_path_to_8(buf, path))
 134                                 error = 0;
 135                 }
 136
 137                 RegCloseKey(hKey);
 138         }
 139
 140         return error;
 141 }
 142
 143 static int win32_find_existing_dirs(
 144         git_buf *out, const wchar_t *tmpl[])
 145 {
 146         _findfile_path path16;
 147         git_buf buf = GIT_BUF_INIT;
 148
 149         git_buf_clear(out);
 150
 151         for (; *tmpl != NULL; tmpl++) {
 152                 if (!git_win32__expand_path(&path16, *tmpl) &&
 153                         path16.path[0] != L'%' &&
 154                         !_waccess(path16.path, F_OK))
 155                 {
 156                         win32_path_to_8(&buf, path16.path);
 157
 158                         if (buf.size)
 159                                 git_buf_join(out, GIT_PATH_LIST_SEPARATOR, out->ptr, buf.ptr);
 160                 }
 161         }
 162
 163         git_buf_dispose(&buf);
 164
 165         return (git_buf_oom(out) ? -1 : 0);
 166 }
 167
 168 int git_win32__find_system_dirs(git_buf *out, const wchar_t *subdir)
 169 {
 170         git_buf buf = GIT_BUF_INIT;
 171
 172         /* directories where git.exe & git.cmd are found */
 173         if (!win32_find_git_in_path(&buf, L"git.exe", subdir) && buf.size)
 174                 git_buf_set(out, buf.ptr, buf.size);
 175         else
 176                 git_buf_clear(out);
 177
 178         if (!win32_find_git_in_path(&buf, L"git.cmd", subdir) && buf.size)
 179                 git_buf_join(out, GIT_PATH_LIST_SEPARATOR, out->ptr, buf.ptr);
 180
 181         /* directories where git is installed according to registry */
 182         if (!win32_find_git_in_registry(
 183                         &buf, HKEY_CURRENT_USER, REG_MSYSGIT_INSTALL_LOCAL, subdir) && buf.size)
 184                 git_buf_join(out, GIT_PATH_LIST_SEPARATOR, out->ptr, buf.ptr);
 185
 186         if (!win32_find_git_in_registry(
 187                         &buf, HKEY_LOCAL_MACHINE, REG_MSYSGIT_INSTALL, subdir) && buf.size)
 188                 git_buf_join(out, GIT_PATH_LIST_SEPARATOR, out->ptr, buf.ptr);
 189
 190         git_buf_dispose(&buf);
 191
 192         return (git_buf_oom(out) ? -1 : 0);
 193 }
 194
 195 int git_win32__find_global_dirs(git_buf *out)
 196 {
 197         static const wchar_t *global_tmpls[4] = {
 198                 L"%HOME%\\",
 199                 L"%HOMEDRIVE%%HOMEPATH%\\",
 200                 L"%USERPROFILE%\\",
 201                 NULL,
 202         };
 203
 204         return win32_find_existing_dirs(out, global_tmpls);
 205 }
 206
 207 int git_win32__find_xdg_dirs(git_buf *out)
 208 {
 209         static const wchar_t *global_tmpls[7] = {
 210                 L"%XDG_CONFIG_HOME%\\git",
 211                 L"%APPDATA%\\git",
 212                 L"%LOCALAPPDATA%\\git",
 213                 L"%HOME%\\.config\\git",
 214                 L"%HOMEDRIVE%%HOMEPATH%\\.config\\git",
 215                 L"%USERPROFILE%\\.config\\git",
 216                 NULL,
 217         };
 218
 219         return win32_find_existing_dirs(out, global_tmpls);
 220 }
 221
 222 int git_win32__find_programdata_dirs(git_buf *out)
 223 {
 224         static const wchar_t *programdata_tmpls[2] = {
 225                 L"%PROGRAMDATA%\\Git",
 226                 NULL,
 227         };
 228
 229         return win32_find_existing_dirs(out, programdata_tmpls);
 230 }