Add usage message and reading of the Registry

Change-Id: Iddebcaaaeee234321a71569e80f939e8c324513d
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/103914
Tested-by: Tor Lillqvist <tml@collabora.com>
Reviewed-by: Tor Lillqvist <tml@collabora.com>

1 files changed, 90 insertions, 17 deletions

diff --git a/solenv/wsl/wsl-lo-helper.cpp b/solenv/wsl/wsl-lo-helper.cpp
index 9fe780dc12f6..0b641ceb04bd 100644
--- a/solenv/wsl/wsl-lo-helper.cpp
+++ b/solenv/wsl/wsl-lo-helper.cpp
@@ -12,9 +12,7 @@
  *
  * It is a Win32 program, not a Linux (WSL) one.
  *
- * So far just one function: Convert a full Windows pathname to 8.3 format (if present). WSL does
- * not seem to have that functionality built-in, and doing it through some invocations of cmd.exe or
- * a .bat file from WSL seems very complex.
+ * Compile as: cl -MD wsl-lo-helper.cpp advapi32.lib
  */
 
 #include <cstdio>
@@ -22,12 +20,32 @@
 
 #include <Windows.h>
 
+static void print_result(const wchar_t* argv0, const wchar_t* result)
+{
+    char output[1000];
+    if (WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, result, -1, output, sizeof(output), NULL,
+                            NULL)
+        == 0)
+    {
+        fprintf(stderr, "%S --8.3: Could not convert result to UTF-8.\n", argv0);
+        exit(1);
+    }
+
+    // Intentionally output no newline at end
+    printf("%s", output);
+    fflush(stdout);
+}
+
 int wmain(int argc, wchar_t** argv)
 {
     if (argc <= 1)
     {
-        fprintf(stderr, "%S: Arguments expected\n", argv[0]);
-        return 1;
+        fprintf(stderr, "%S: Usage:\n", argv[0]);
+        fprintf(stderr, "%S --8.3 <windows-pathname>\n", argv[0]);
+        fprintf(stderr, "    Print the 8.3 form of a Windows pathnam. Fail it not present.\n");
+        fprintf(stderr, "%S --read-registry [32|64] <path>\n", argv[0]);
+        fprintf(stderr, "    Read a string value from HKLM in the Registry and print it.\n");
+        exit(1);
     }
 
     if (wcscmp(argv[1], L"--8.3") == 0)
@@ -35,7 +53,7 @@ int wmain(int argc, wchar_t** argv)
         if (argc != 3)
         {
             fprintf(stderr, "%S --8.3: One pathname argument expected\n", argv[0]);
-            return 1;
+            exit(1);
         }
 
         // The argument should be a pathname in Windows format. The
@@ -45,22 +63,77 @@ int wmain(int argc, wchar_t** argv)
         wchar_t woutput[1000];
         if (GetShortPathNameW(argv[2], woutput, sizeof(woutput) / sizeof(woutput[0])) == 0)
         {
-            fprintf(stderr, "%S --8.3: Could not get short pathname\n", argv[0]);
-            return 1;
+            fprintf(stderr, "%S --8.3: Could not get short pathname.\n", argv[0]);
+            exit(1);
+        }
+
+        print_result(argv[0], woutput);
+    }
+    else if (wcscmp(argv[1], L"--read-registry") == 0)
+    {
+        if (argc != 4)
+        {
+            fprintf(stderr, "%S --read-registry: Bitness and path arguments expected.\n", argv[0]);
+            exit(1);
         }
 
-        char output[1000];
-        if (WideCharToMultiByte(CP_UTF8, WC_ERR_INVALID_CHARS, woutput, -1, output, sizeof(output),
-                                NULL, NULL)
-            == 0)
+        REGSAM sam;
+        if (wcscmp(argv[2], L"32") == 0)
+            sam = KEY_WOW64_32KEY;
+        else if (wcscmp(argv[2], L"64") == 0)
+            sam = KEY_WOW64_64KEY;
+        else
         {
-            fprintf(stderr, "%S --8.3: Could not convert result to UTF-8\n", argv[0]);
-            return 1;
+            fprintf(stderr, "%S --read-registry: Use 32 or 64.\n", argv[0]);
+            exit(1);
         }
 
-        // Intentionally output no newline at end
-        printf("%s", output);
-        fflush(stdout);
+        wchar_t* path = wcsdup(argv[3]);
+
+        for (wchar_t* p = path; *p != L'\0'; p++)
+            if (*p == '/')
+                *p = '\\';
+
+        DWORD type;
+        wchar_t result[1000];
+        DWORD count = sizeof(result);
+
+        wchar_t* last_backslash = wcsrchr(path, L'\\');
+        if (last_backslash == NULL)
+        {
+            fprintf(stderr, "%S: Invalid path to value in the Registry.\n", argv[0]);
+            exit(1);
+        }
+
+        *last_backslash = L'\0';
+        wchar_t* value = last_backslash + 1;
+
+        HKEY key;
+        if (RegOpenKeyExW(HKEY_LOCAL_MACHINE, path, 0, KEY_QUERY_VALUE | sam, &key)
+            != ERROR_SUCCESS)
+        {
+            fprintf(stderr, "%S: Opening key %S in %S-bit Registry failed.\n", argv[0], path,
+                    argv[2]);
+            exit(1);
+        }
+
+        if (RegQueryValueExW(key, value, NULL, &type, (LPBYTE)result, &count) != ERROR_SUCCESS)
+        {
+            fprintf(stderr, "%S: Reading value %S\\%S from %S-bit Registry failed.\n", argv[0],
+                    path, value, argv[2]);
+            exit(1);
+        }
+        if (type != REG_SZ)
+        {
+            fprintf(stderr, "%S: Value %S\\%S is not a string.\n", argv[0], path, value);
+            exit(1);
+        }
+        print_result(argv[0], result);
+    }
+    else
+    {
+        fprintf(stderr, "%S: Unrecognized sub-command %S.\n", argv[0], argv[1]);
+        exit(1);
     }
 
     return 0;