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#include "pkg_db.h"
#include "util.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/wait.h>
#define PKG_DB "../packages"
#define PKG_DB_LEN (sizeof(PKG_DB) - 1)
#define PKG_INFO_CMD "./get_pkg_attrs.sh"
bool load_package_info(package_info_t* info, char* pkgid) {
memset(info, 0, sizeof(*info));
size_t pkgid_len = strlen(pkgid);
// construct package description directory path and ensure it exists
// pkg_dir = "PKG_DB/pkgid"
size_t pkg_dir_len = PKG_DB_LEN + pkgid_len + 1;
char* pkg_dir = emalloc(pkg_dir_len + 1, "pkg_dir");
{
memcpy(pkg_dir, PKG_DB, PKG_DB_LEN);
pkg_dir[PKG_DB_LEN] = '/';
memcpy(pkg_dir + PKG_DB_LEN + 1, pkgid, pkgid_len);
pkg_dir[pkg_dir_len] = '\0';
if (access(pkg_dir, F_OK) != 0) {
eprintf("Package '%s' not found\n", pkgid);
free(pkg_dir);
return false;
}
}
// construct package description script path and ensure it exists
// script_path = "pkg_dir/pkgid.sh"
size_t script_path_len = pkg_dir_len + pkgid_len + 4;
info->script_path = emalloc(script_path_len + 1, "info->script_path");
{
memcpy(info->script_path, pkg_dir, pkg_dir_len);
info->script_path[pkg_dir_len] = '/';
memcpy(&info->script_path[pkg_dir_len + 1], pkgid, pkgid_len);
memcpy(&info->script_path[script_path_len - 3], ".sh", 4);
free(pkg_dir);
if (access(info->script_path, F_OK) != 0) {
eprintf("Package '%s' broken, doesn't have description script\n", pkgid);
free(info->script_path);
return false;
}
}
// PIPE and FORK to run get pkg attrs script
int pipefds[2] = {0};
if (pipe(pipefds) < 0) error_out("failed to pipe: %s", strerror(errno));
pid_t pid = fork();
if (pid < 0) error_out("failed to fork: %s", strerror(errno));
// child proc
if (pid == 0) {
// write my stdout the the pipe
close(pipefds[0]);
dup2(pipefds[1], STDOUT_FILENO);
close(pipefds[1]);
// exec into get attr script
char* argv[] = { PKG_INFO_CMD, info->script_path, NULL };
char* envp[] = { NULL };
execve(PKG_INFO_CMD, argv, envp);
error_out("execve failed");
}
// wait for child to finish
int wstatus;
if (waitpid(pid, &wstatus, 0) < 0) error_out("waitpid failed: %s", strerror(errno));
if (WEXITSTATUS(wstatus) != 0) error_out("failed to execute get pkg attr script");
// read all bytes from pipe
ssize_t bytes_read = read(pipefds[0], info->package_attrs, sizeof(info->package_attrs));
if (bytes_read < 0) error_out("Failed to read from pipe");
// read attributes from pipe data
for (int i = 0; i < bytes_read;) {
char atype = info->package_attrs[i];
i++;
switch (atype) {
case 'i':
info->attrs.id = &info->package_attrs[i];
break;
case 'n':
info->attrs.name = &info->package_attrs[i];
break;
case 'd':
info->attrs.desc = &info->package_attrs[i];
break;
}
for(;info->package_attrs[i] && i < bytes_read; i++);
i++;
}
return true;
}
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