GM: fix --mismatchPath option

gm/gmmain.cpp

Index: gm/gmmain.cpp
===================================================================
--- gm/gmmain.cpp	(revision 8959)
+++ gm/gmmain.cpp	(working copy)
@@ -1640,6 +1640,26 @@
     return total;
 }
 
+bool prepare_subdirectories(const char *root, bool useFileHierarchy,
+                            const SkTDArray<size_t> &configs);
+bool prepare_subdirectories(const char *root, bool useFileHierarchy,
+                            const SkTDArray<size_t> &configs) {
+    if (!sk_mkdir(root)) {
+        return false;
+    }
+    if (useFileHierarchy) {
+        for (int i = 0; i < configs.count(); i++) {
+            ConfigData config = gRec[configs[i]];
+            SkString subdir;
+            subdir.appendf("%s%c%s", root, SkPATH_SEPARATOR, config.fName);
+            if (!sk_mkdir(subdir.c_str())) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
 int tool_main(int argc, char** argv);
 int tool_main(int argc, char** argv) {
 
@@ -1851,6 +1871,9 @@
         if (FLAGS_writePath.count() == 1) {
             gm_fprintf(stdout, "writing to %s\n", FLAGS_writePath[0]);
         }
+        if (NULL != gmmain.fMismatchPath) {
+            gm_fprintf(stdout, "writing mismatches to %s\n", gmmain.fMismatchPath);
+        }
         if (FLAGS_writePicturePath.count() == 1) {
             gm_fprintf(stdout, "writing pictures to %s\n", FLAGS_writePicturePath[0]);
         }
@@ -1872,19 +1895,13 @@
 
     // If we will be writing out files, prepare subdirectories.
     if (FLAGS_writePath.count() == 1) {
-        if (!sk_mkdir(FLAGS_writePath[0])) {
+        if (!prepare_subdirectories(FLAGS_writePath[0], gmmain.fUseFileHierarchy, configs)) {
             return -1;
         }
-        if (gmmain.fUseFileHierarchy) {
-            for (int i = 0; i < configs.count(); i++) {
-                ConfigData config = gRec[configs[i]];
-                SkString subdir;
-                subdir.appendf("%s%c%s", FLAGS_writePath[0], SkPATH_SEPARATOR,
-                               config.fName);
-                if (!sk_mkdir(subdir.c_str())) {
-                    return -1;
-                }
-            }
+    }
+    if (NULL != gmmain.fMismatchPath) {
+        if (!prepare_subdirectories(gmmain.fMismatchPath, gmmain.fUseFileHierarchy, configs)) {

[epoger, 2013/05/02 16:34:34]

Patchset 3 creates subdirectories for mismatchPath like it does for writePath,
and now the results confirm that this allows mismatches to be written out.

The problem, though, is that the mismatchPath subdirectories are created even if
there are no mismatches!  This can be misleading ("hey, I see that the directory
mismatchPath/8888 exists, that must mean that there are some 8888 mismatches").

I'm going to see if there is some relatively simple way to only create the
directory structures when they are needed to write out a file.

+            return -1;
         }
     }