llvm-6502/lib/System/Unix/Program.inc
Reid Spencer 2565943289 Clean up the interface and implementation of sys::Program so that it is
cleanly dissociated from the sys::Path class.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16315 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-13 21:48:44 +00:00

137 lines
4.1 KiB
C++

//===- llvm/System/Unix/Program.cpp -----------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Reid Spencer and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Unix specific portion of the Program class.
//
//===----------------------------------------------------------------------===//
//===----------------------------------------------------------------------===//
//=== WARNING: Implementation here must contain only generic UNIX code that
//=== is guaranteed to work on *all* UNIX variants.
//===----------------------------------------------------------------------===//
#include <llvm/Config/config.h>
#include "Unix.h"
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif
extern char** environ;
namespace llvm {
using namespace sys;
// This function just uses the PATH environment variable to find the program.
Path
Program::FindProgramByName(const std::string& progName) {
// Check some degenerate cases
if (progName.length() == 0) // no program
return Path();
Path temp;
if (!temp.set_file(progName)) // invalid name
return Path();
if (temp.executable()) // already executable as is
return temp;
// At this point, the file name is valid and its not executable
// Get the path. If its empty, we can't do anything to find it.
const char *PathStr = getenv("PATH");
if (PathStr == 0)
return Path();
// Now we have a colon separated list of directories to search; try them.
unsigned PathLen = strlen(PathStr);
while (PathLen) {
// Find the first colon...
const char *Colon = std::find(PathStr, PathStr+PathLen, ':');
// Check to see if this first directory contains the executable...
Path FilePath;
if (FilePath.set_directory(std::string(PathStr,Colon))) {
FilePath.append_file(progName);
if (FilePath.executable())
return FilePath; // Found the executable!
}
// Nope it wasn't in this directory, check the next path in the list!
PathLen -= Colon-PathStr;
PathStr = Colon;
// Advance past duplicate colons
while (*PathStr == ':') {
PathStr++;
PathLen--;
}
}
return Path();
}
//
int
Program::ExecuteAndWait(const Path& path,
const std::vector<std::string>& args) {
if (!path.executable())
throw path.get() + " is not executable";
#ifdef HAVE_SYS_WAIT_H
// Create local versions of the parameters that can be passed into execve()
// without creating const problems.
const char* argv[ args.size() + 2 ];
unsigned index = 0;
std::string progname(path.getLast());
argv[index++] = progname.c_str();
for (unsigned i = 0; i < args.size(); i++)
argv[index++] = args[i].c_str();
argv[index] = 0;
// Create a child process.
switch (fork()) {
// An error occured: Return to the caller.
case -1:
ThrowErrno(std::string("Couldn't execute program '") + path.get() + "'");
break;
// Child process: Execute the program.
case 0:
execve (path.c_str(), (char** const)argv, environ);
// If the execve() failed, we should exit and let the parent pick up
// our non-zero exit status.
exit (errno);
// Parent process: Break out of the switch to do our processing.
default:
break;
}
// Parent process: Wait for the child process to terminate.
int status;
if ((::wait (&status)) == -1)
ThrowErrno(std::string("Failed waiting for program '") + path.get() + "'");
// If the program exited normally with a zero exit status, return success!
if (WIFEXITED (status))
return WEXITSTATUS(status);
else if (WIFSIGNALED(status))
throw std::string("Program '") + path.get() + "' received terminating signal.";
else
return 0;
#else
throw std::string("Program::ExecuteAndWait not implemented on this platform!\n");
#endif
}
}
// vim: sw=2 smartindent smarttab tw=80 autoindent expandtab