Allow more options for setting boolean flag values in SkFlags.

tools/SkFlags.h

Index: tools/SkFlags.h
diff --git a/tools/SkFlags.h b/tools/SkFlags.h
index 79cc8788a3b26f93393f519ce0014ebbe79dd532..237d11ce2e77a78839d5decc9632a63dea06d1e7 100644
--- a/tools/SkFlags.h
+++ b/tools/SkFlags.h
@@ -37,8 +37,13 @@
  *
  *  which will initially be set to false, and can be set to true by using the
  *  flag "--boolean" on the commandline. "--noboolean" will set FLAGS_boolean
- *  to false. (Single dashes are also permitted for this and other flags.) The
- *  helpString will be printed if the help flag (-h or -help) is used.
+ *  to false. FLAGS_boolean can also be set using "--boolean=true" or
+ *  "--boolean true" (where "true" can be replaced by "false", "TRUE", "FALSE",
+ *  "1" or "0").
+ *
+ *  Single dashes are also permitted for this and other flags.
+ *
+ *  The helpString will be printed if the help flag (-h or -help) is used.

[reed1, 2013/03/20 20:09:41]

do you mean --help or -help?

[scroggo, 2013/03/20 21:12:05]

In reality, I mean --help or -help or -h or --h. For simplicity, I included only
the ones that are standard (two dashes for multiple characters, one for single
characters).

  *
  *  Similarly, the line
  *
@@ -227,8 +232,38 @@ public:
     }
 
     /**
-     *  Returns true if the string matches this flag. For a bool, also sets the
-     *  value, since a bool is specified as true or false by --name or --noname.
+     *  Check to see whether string represents a boolean value.
+     *  @param string C style string to parse.
+     *  @param result Pointer to a boolean which will be set to the value in the string, if the
+     *      string represents a boolean.
+     *  @param boolean True if the string represents a boolean, false otherwise.
+     */
+    static bool ParseBoolArg(const char* string, bool* result) {

[reed1, 2013/03/20 20:09:41]

Is it cleaner to use a small table of strings for these, instead of explicit
||s?

[scroggo, 2013/03/20 21:12:05]

Done.

+        SkString parameter(string);
+        if (parameter.equals("1") || parameter.equals("TRUE") || parameter.equals("true")) {
+            *result = true;
+            return true;
+        }
+        if (parameter.equals("0") || parameter.equals("FALSE") || parameter.equals("false")) {
+            *result = false;
+            return true;
+        }
+        SkDebugf("Parameter \"%s\" not supported.\n", string);
+        return false;
+    }
+
+    /**
+     *  Returns true if the string matches this flag.
+     *  For a boolean flag, also sets the value, since a boolean flag can be set in a number of ways
+     *  without looking at the following string:
+     *      --name
+     *      --noname
+     *      --name=true
+     *      --name=false
+     *      --name=1
+     *      --name=0
+     *      --name=TRUE
+     *      --name=FALSE
      */
     bool match(const char* string) {
         if (SkStrStartsWith(string, '-') && strlen(string) > 1) {
@@ -251,6 +286,17 @@ public:
                     }
                     return false;
                 }
+                int equalIndex = SkStrFind(string, "=");
+                if (equalIndex > 0) {
+                    // The string has an equal sign. Check to see if the string matches.
+                    SkString flag(string, equalIndex);
+                    if (flag.equals(fName) || flag.equals(fShortName)) {
+                        // Check to see if the remainder beyond the equal sign is true or false:
+                        string += equalIndex + 1;
+                        ParseBoolArg(string, fBoolValue);
+                        return true;
+                    }
+                }
             }
             return fName.equals(string) || fShortName.equals(string);
         } else {
@@ -294,6 +340,14 @@ public:
         }
     }
 
+    void setBool(bool value) {
+        if (kBool_FlagType == fFlagType) {
+            *fBoolValue = value;
+        } else {
+            SkASSERT(!"Can only call setBool on kBool_FlagType");
+        }
+    }
+
     SkFlagInfo* next() { return fNext; }
 
     const SkString& name() const { return fName; }