waybar/include/util/command.hpp
2020-03-30 10:36:24 +02:00

105 lines
2.0 KiB
C++

#pragma once
#include <giomm.h>
#include <sys/wait.h>
#include <unistd.h>
namespace waybar::util::command {
struct res {
int exit_code;
std::string out;
};
inline std::string read(FILE* fp) {
std::array<char, 128> buffer = {0};
std::string output;
while (feof(fp) == 0) {
if (fgets(buffer.data(), 128, fp) != nullptr) {
output += buffer.data();
}
}
// Remove last newline
if (!output.empty() && output[output.length() - 1] == '\n') {
output.erase(output.length() - 1);
}
return output;
}
inline int close(FILE* fp, pid_t pid) {
int stat;
fclose(fp);
while (waitpid(pid, &stat, 0) == -1) {
if (errno != EINTR) {
stat = 0;
break;
}
}
return stat;
}
inline FILE* open(const std::string cmd, int& pid) {
if (cmd == "") return nullptr;
int fd[2];
pipe(fd);
pid_t child_pid = fork();
if (child_pid < 0) {
printf("Unable to exec cmd %s, error %s", cmd.c_str(), strerror(errno));
return nullptr;
}
if (!child_pid) {
::close(fd[0]);
dup2(fd[1], 1);
setpgid(child_pid, child_pid);
execl("/bin/sh", "sh", "-c", cmd.c_str(), (char*)0);
exit(0);
} else {
::close(fd[1]);
}
pid = child_pid;
return fdopen(fd[0], "r");
}
inline struct res exec(std::string cmd) {
int pid;
auto fp = command::open(cmd, pid);
if (!fp) return {-1, ""};
auto output = command::read(fp);
auto stat = command::close(fp, pid);
if (WIFEXITED(stat)) {
return {WEXITSTATUS(stat), output};
}
return {-1, output};
}
inline int32_t forkExec(std::string cmd) {
if (cmd == "") return -1;
int32_t pid = fork();
if (pid < 0) {
printf("Unable to exec cmd %s, error %s", cmd.c_str(), strerror(errno));
return pid;
}
// Child executes the command
if (!pid) {
setpgid(pid, pid);
signal(SIGCHLD, SIG_DFL);
execl("/bin/sh", "sh", "-c", cmd.c_str(), (char*)0);
exit(0);
} else {
signal(SIGCHLD,SIG_IGN);
}
return pid;
}
} // namespace waybar::util::command