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// Executable Name |
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// |
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// Douglas Thrift |
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// |
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// $Id$ |
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|
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#include <iostream> |
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#include <string> |
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#include <sstream> |
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#include <cstdio> |
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|
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extern "C" |
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{ |
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#include <sys/param.h> |
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#include <unistd.h> |
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#include <sys/types.h> |
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#include <sys/stat.h> |
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} |
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|
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#include <cstdlib> |
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|
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int main(int argc, char* argv[]) |
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{ |
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std::string program(argv[0]); |
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|
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if (program.find('/') == std::string::npos) |
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{ |
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std::istringstream path(::getenv("PATH") != NULL ? ::getenv("PATH") |
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: std::string()); |
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|
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do |
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{ |
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std::string candidate; |
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|
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std::getline(path, candidate, ':'); |
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|
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candidate += '/' + program; |
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|
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if (::access(candidate.c_str(), X_OK) == 0) |
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{ |
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struct ::stat file; |
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|
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if (::stat(candidate.c_str(), &file) == 0 |
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&& S_ISREG(file.st_mode) && (::getuid() != 0 |
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|| (file.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0)) |
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{ |
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::lstat(candidate.c_str(), &file); |
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|
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if (S_ISLNK(file.st_mode)) |
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{ |
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char buffer[1024]; |
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int length(::readlink(candidate.c_str(), buffer, 1024)); |
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|
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if (length == -1) |
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{ |
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::perror(argv[0]); |
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|
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return 1; |
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} |
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|
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program.assign(buffer, length); |
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} |
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else program = candidate; |
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|
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break; |
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} |
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} |
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} |
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while (path.good()); |
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} |
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|
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char executable[PATH_MAX]; |
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|
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if (::realpath(program.c_str(), executable) == NULL) |
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{ |
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::perror(argv[0]); |
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|
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return 1; |
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} |
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|
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std::cout << "executable = " << executable << '\n'; |
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|
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return 0; |
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} |
