mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-07 11:33:44 +00:00
82 lines
2.6 KiB
C
82 lines
2.6 KiB
C
|
//===- SystemUtils.h - Utilities to do low-level system stuff --*- C++ -*--===//
|
||
|
|
//
|
||
|
|
// This file contains functions used to do a variety of low-level, often
|
||
|
|
// system-specific, tasks.
|
||
|
|
//
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
|
||
|
|
#include "SysUtils.h"
|
||
|
|
#include "Config/sys/types.h"
|
||
|
|
#include "Config/sys/stat.h"
|
||
|
|
#include "Config/fcntl.h"
|
||
|
|
#include "Config/sys/wait.h"
|
||
|
|
#include "Config/unistd.h"
|
||
|
|
#include "Config/errno.h"
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
|
||
|
|
/// isExecutableFile - This function returns true if the filename specified
|
||
|
|
/// exists and is executable.
|
||
|
|
///
|
||
|
|
bool isExecutableFile(const char *ExeFileName) {
|
||
|
|
struct stat Buf;
|
||
|
|
if (stat(ExeFileName, &Buf))
|
||
|
|
return false; // Must not be executable!
|
||
|
|
|
||
|
|
if (!(Buf.st_mode & S_IFREG))
|
||
|
|
return false; // Not a regular file?
|
||
|
|
|
||
|
|
if (Buf.st_uid == getuid()) // Owner of file?
|
||
|
|
return Buf.st_mode & S_IXUSR;
|
||
|
|
else if (Buf.st_gid == getgid()) // In group of file?
|
||
|
|
return Buf.st_mode & S_IXGRP;
|
||
|
|
else // Unrelated to file?
|
||
|
|
return Buf.st_mode & S_IXOTH;
|
||
|
|
}
|
||
|
|
|
||
|
|
/// FindExecutable - Find a named executable in the directories listed in $PATH.
|
||
|
|
/// If the executable cannot be found, returns NULL.
|
||
|
|
///
|
||
|
|
char *FindExecutable(const char *ExeName) {
|
||
|
|
/* Try to find the executable in the path */
|
||
|
|
const char *PathStr = getenv("PATH");
|
||
|
|
if (PathStr == 0) return "";
|
||
|
|
|
||
|
|
// Now we have a colon separated list of directories to search... try them...
|
||
|
|
unsigned PathLen = strlen(PathStr);
|
||
|
|
while (PathLen) {
|
||
|
|
/* Find the next colon */
|
||
|
|
const char *Colon = strchr(PathStr, ':');
|
||
|
|
|
||
|
|
/* Check to see if this first directory contains the executable... */
|
||
|
|
unsigned DirLen = Colon ? (Colon-PathStr) : strlen(PathStr);
|
||
|
|
char *FilePath = alloca(sizeof(char) * (DirLen+1+strlen(ExeName)+1));
|
||
|
|
unsigned i, e;
|
||
|
|
for (i = 0; i != DirLen; ++i)
|
||
|
|
FilePath[i] = PathStr[i];
|
||
|
|
FilePath[i] = '/';
|
||
|
|
for (i = 0, e = strlen(ExeName); i != e; ++i)
|
||
|
|
FilePath[DirLen + 1 + i] = ExeName[i];
|
||
|
|
FilePath[DirLen + 1 + i] = '\0';
|
||
|
|
if (isExecutableFile(FilePath))
|
||
|
|
return strdup(FilePath); /* Found the executable! */
|
||
|
|
|
||
|
|
/* If Colon is NULL, there are no more colon separators and no more dirs */
|
||
|
|
if (!Colon) break;
|
||
|
|
|
||
|
|
/* Nope, it wasn't in this directory, check the next range! */
|
||
|
|
PathLen -= DirLen;
|
||
|
|
PathStr = Colon;
|
||
|
|
while (*PathStr == ':') { /* Advance past colons */
|
||
|
|
PathStr++;
|
||
|
|
PathLen--;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Advance past the colon */
|
||
|
|
++Colon;
|
||
|
|
}
|
||
|
|
|
||
|
|
// If we fell out, we ran out of directories in PATH to search, return failure
|
||
|
|
return NULL;
|
||
|
|
}
|