source: MondoRescue/branches/2.2.9/mindi-busybox/archival/libarchive/data_extract_to_command.c@ 2725

/* vi: set sw=4 ts=4: */
/*
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */

#include "libbb.h"
#include "archive.h"

enum {
    //TAR_FILETYPE,
    TAR_MODE,
    TAR_FILENAME,
    TAR_REALNAME,
#if ENABLE_FEATURE_TAR_UNAME_GNAME
    TAR_UNAME,
    TAR_GNAME,
#endif
    TAR_SIZE,
    TAR_UID,
    TAR_GID,
    TAR_MAX,
};

static const char *const tar_var[] = {
    // "FILETYPE",
    "MODE",
    "FILENAME",
    "REALNAME",
#if ENABLE_FEATURE_TAR_UNAME_GNAME
    "UNAME",
    "GNAME",
#endif
    "SIZE",
    "UID",
    "GID",
};

static void xputenv(char *str)
{
    if (putenv(str))
        bb_error_msg_and_die(bb_msg_memory_exhausted);
}

static void str2env(char *env[], int idx, const char *str)
{
    env[idx] = xasprintf("TAR_%s=%s", tar_var[idx], str);
    xputenv(env[idx]);
}

static void dec2env(char *env[], int idx, unsigned long long val)
{
    env[idx] = xasprintf("TAR_%s=%llu", tar_var[idx], val);
    xputenv(env[idx]);
}

static void oct2env(char *env[], int idx, unsigned long val)
{
    env[idx] = xasprintf("TAR_%s=%lo", tar_var[idx], val);
    xputenv(env[idx]);
}

void FAST_FUNC data_extract_to_command(archive_handle_t *archive_handle)
{
    file_header_t *file_header = archive_handle->file_header;

#if 0 /* do we need this? ENABLE_FEATURE_TAR_SELINUX */
    char *sctx = archive_handle->tar__next_file_sctx;
    if (!sctx)
        sctx = archive_handle->tar__global_sctx;
    if (sctx) { /* setfscreatecon is 4 syscalls, avoid if possible */
        setfscreatecon(sctx);
        free(archive_handle->tar__next_file_sctx);
        archive_handle->tar__next_file_sctx = NULL;
    }
#endif

    if ((file_header->mode & S_IFMT) == S_IFREG) {
        pid_t pid;
        int p[2], status;
        char *tar_env[TAR_MAX];

        memset(tar_env, 0, sizeof(tar_env));

        xpipe(p);
        pid = BB_MMU ? xfork() : xvfork();
        if (pid == 0) {
            /* Child */
            /* str2env(tar_env, TAR_FILETYPE, "f"); - parent should do it once */
            oct2env(tar_env, TAR_MODE, file_header->mode);
            str2env(tar_env, TAR_FILENAME, file_header->name);
            str2env(tar_env, TAR_REALNAME, file_header->name);
#if ENABLE_FEATURE_TAR_UNAME_GNAME
            str2env(tar_env, TAR_UNAME, file_header->tar__uname);
            str2env(tar_env, TAR_GNAME, file_header->tar__gname);
#endif
            dec2env(tar_env, TAR_SIZE, file_header->size);
            dec2env(tar_env, TAR_UID, file_header->uid);
            dec2env(tar_env, TAR_GID, file_header->gid);
            close(p[1]);
            xdup2(p[0], STDIN_FILENO);
            signal(SIGPIPE, SIG_DFL);
            execl(DEFAULT_SHELL, DEFAULT_SHELL_SHORT_NAME, "-c", archive_handle->tar__to_command, NULL);
            bb_perror_msg_and_die("can't execute '%s'", DEFAULT_SHELL);
        }
        close(p[0]);
        /* Our caller is expected to do signal(SIGPIPE, SIG_IGN)
         * so that we don't die if child don't read all the input: */
        bb_copyfd_exact_size(archive_handle->src_fd, p[1], -file_header->size);
        close(p[1]);

        if (safe_waitpid(pid, &status, 0) == -1)
            bb_perror_msg_and_die("waitpid");
        if (WIFEXITED(status) && WEXITSTATUS(status))
            bb_error_msg_and_die("'%s' returned status %d",
                archive_handle->tar__to_command, WEXITSTATUS(status));
        if (WIFSIGNALED(status))
            bb_error_msg_and_die("'%s' terminated on signal %d",
                archive_handle->tar__to_command, WTERMSIG(status));

        if (!BB_MMU) {
            int i;
            for (i = 0; i < TAR_MAX; i++) {
                if (tar_env[i])
                    bb_unsetenv_and_free(tar_env[i]);
            }
        }
    }

#if 0 /* ENABLE_FEATURE_TAR_SELINUX */
    if (sctx)
        /* reset the context after creating an entry */
        setfscreatecon(NULL);
#endif
}