process: add Start(program, vector<char*>)

Same thing as the va_list but takes a std::vector of arguments instead.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>

2 files changed, 35 insertions, 6 deletions

diff --git a/include/xorg/gtest/xorg-gtest-process.h b/include/xorg/gtest/xorg-gtest-process.h
index 47aefcf..0b721ce 100644
--- a/include/xorg/gtest/xorg-gtest-process.h
+++ b/include/xorg/gtest/xorg-gtest-process.h
@@ -93,6 +93,22 @@ class Process {
   /**
    * Starts a program as a child process.
    *
+   * See 'man execvp' for further information on the elements in
+   * the vector.
+   *
+   * @param program The program to start.
+   * @param args Vector of arguments passed to the program.
+   *
+   * @throws std::runtime_error on failure.
+   *
+   * @post If successful: Child process forked and program started.
+   * @post If successful: Subsequent calls to Pid() return child process pid.
+   */
+  void Start(const std::string& program, const std::vector<std::string> &args);
+
+  /**
+   * Starts a program as a child process.
+   *
    * See 'man execvp' for further information on the variadic argument list.
    *
    * @param program The program to start.
diff --git a/src/process.cpp b/src/process.cpp
index e79b694..7b60afc 100644
--- a/src/process.cpp
+++ b/src/process.cpp
@@ -48,7 +48,7 @@ xorg::testing::Process::Process() : d_(new Private) {
   d_->pid = -1;
 }
 
-void xorg::testing::Process::Start(const std::string& program, va_list args) {
+void xorg::testing::Process::Start(const std::string &program, const std::vector<std::string> &argv) {
   if (d_->pid != -1)
     throw std::runtime_error("Attempting to start an already started process");
 
@@ -61,18 +61,31 @@ void xorg::testing::Process::Start(const std::string& program, va_list args) {
     close(1);
     close(2);
 
-    std::vector<char*> argv;
+    std::vector<char*> args;
+    std::vector<std::string>::const_iterator it;
 
-    do
-      argv.push_back(va_arg(args, char*));
-    while (argv.back());
+    for (it = argv.begin(); it != argv.end(); it++)
+      if (!it->empty())
+        args.push_back(strdup(it->c_str()));
+    args.push_back(NULL);
 
-    execvp(program.c_str(), &argv[0]);
+    execvp(program.c_str(), &args[0]);
 
     throw std::runtime_error("Failed to start process");
   }
 }
 
+void xorg::testing::Process::Start(const std::string& program, va_list args) {
+  std::vector<std::string> argv;
+
+  do {
+    std::string arg(va_arg(args, char*));
+    argv.push_back(arg);
+  } while (!argv.back().empty());
+
+  Start(program, argv);
+}
+
 void xorg::testing::Process::Start(const std::string& program, ...) {
   va_list list;
   va_start(list, program);