[llvm] r216411 - Refactor argument serialization logic when executing process. NFC.

[Rafael Espindola]

Author: rafael
Date: Mon Aug 25 17:15:06 2014
New Revision: 216411

URL: http://llvm.org/viewvc/llvm-project?rev=216411&view=rev
Log:
Refactor argument serialization logic when executing process. NFC.

This patch refactors the argument serialization logic used in the Execute
function, used to launch new Windows processes. There is a critical step that
joins char** arguments into a single string, building the command line used to
launch the new process, and the readability of this code is improved if this
part is refactored in its own helper function.

Patch by Rafael Auler!

Modified:
    llvm/trunk/lib/Support/Windows/Program.inc

Modified: llvm/trunk/lib/Support/Windows/Program.inc
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/Windows/Program.inc?rev=216411&r1=216410&r2=216411&view=diff
==============================================================================
--- llvm/trunk/lib/Support/Windows/Program.inc (original)
+++ llvm/trunk/lib/Support/Windows/Program.inc Mon Aug 25 17:15:06 2014
@@ -166,19 +166,7 @@ static unsigned int ArgLenWithQuotes(con
 
 }
 
-static bool Execute(ProcessInfo &PI, StringRef Program, const char **args,
-                    const char **envp, const StringRef **redirects,
-                    unsigned memoryLimit, std::string *ErrMsg) {
-  if (!sys::fs::can_execute(Program)) {
-    if (ErrMsg)
-      *ErrMsg = "program not executable";
-    return false;
-  }
-
-  // Windows wants a command line, not an array of args, to pass to the new
-  // process.  We have to concatenate them all, while quoting the args that
-  // have embedded spaces (or are empty).
-
+static std::unique_ptr<char[]> flattenArgs(const char **args) {
   // First, determine the length of the command line.
   unsigned len = 0;
   for (unsigned i = 0; args[i]; i++) {
@@ -216,6 +204,22 @@ static bool Execute(ProcessInfo &PI, Str
   }
 
   *p = 0;
+  return command;
+}
+
+static bool Execute(ProcessInfo &PI, StringRef Program, const char **args,
+                    const char **envp, const StringRef **redirects,
+                    unsigned memoryLimit, std::string *ErrMsg) {
+  if (!sys::fs::can_execute(Program)) {
+    if (ErrMsg)
+      *ErrMsg = "program not executable";
+    return false;
+  }
+
+  // Windows wants a command line, not an array of args, to pass to the new
+  // process.  We have to concatenate them all, while quoting the args that
+  // have embedded spaces (or are empty).
+  std::unique_ptr<char[]> command = flattenArgs(args);
 
   // The pointer to the environment block for the new process.
   std::vector<wchar_t> EnvBlock;