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* along with this program. If not, see
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* <http://www.gnu.org/licenses/>.
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* Contact the authors at <mandos@recompile.se>.
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* Contact the authors at <mandos@fukt.bsnet.se>.
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
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asprintf(), O_CLOEXEC */
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#include <stddef.h> /* size_t, NULL */
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#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
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#include <stdbool.h> /* bool, true, false */
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#include <stdio.h> /* fileno(), fprintf(),
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stderr, STDOUT_FILENO, fclose() */
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#include <sys/types.h> /* fstat(), struct stat, waitpid(),
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WIFEXITED(), WEXITSTATUS(), wait(),
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pid_t, uid_t, gid_t, getuid(),
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stderr, STDOUT_FILENO */
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#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
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stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
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uid_t, gid_t, getuid(), getgid(),
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#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
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FD_SET(), FD_ISSET(), FD_CLR */
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#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
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WEXITSTATUS(), WTERMSIG() */
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#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
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WEXITSTATUS(), WTERMSIG(),
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#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
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#include <iso646.h> /* and, or, not */
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#include <dirent.h> /* struct dirent, scandirat() */
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#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, write(), STDOUT_FILENO,
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struct stat, fstat(), close(),
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setgid(), setuid(), S_ISREG(),
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faccessat() pipe2(), fork(),
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_exit(), dup2(), fexecve(), read()
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#include <dirent.h> /* DIR, struct dirent, fdopendir(),
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readdir(), closedir(), dirfd() */
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#include <unistd.h> /* struct stat, stat(), S_ISREG(),
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fcntl(), setuid(), setgid(),
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F_GETFD, F_SETFD, FD_CLOEXEC,
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access(), pipe(), fork(), close()
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dup2(), STDOUT_FILENO, _exit(),
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execv(), write(), read(),
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, openat(), scandirat(),
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#include <string.h> /* strsep, strlen(), strsignal(),
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strcmp(), strncmp() */
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#include <string.h> /* strsep, strlen(), asprintf(),
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strsignal(), strcmp(), strncmp() */
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#include <errno.h> /* errno */
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#include <argp.h> /* struct argp_option, struct
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argp_state, struct argp,
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plugin *p = getplugin(arg);
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p->disabled = false;
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case 128: /* --plugin-dir */
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plugindir = strdup(arg);
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if(plugindir != NULL){
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case 129: /* --config-file */
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/* This is already done by parse_opt_config_file() */
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case 130: /* --userid */
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tmp_id = strtoimax(arg, &tmp, 10);
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tmpmax = strtoimax(arg, &tmp, 10);
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if(errno != 0 or tmp == arg or *tmp != '\0'
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or tmp_id != (uid_t)tmp_id){
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or tmpmax != (uid_t)tmpmax){
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argp_error(state, "Bad user ID number: \"%s\", using %"
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PRIdMAX, arg, (intmax_t)uid);
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case 131: /* --groupid */
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tmp_id = strtoimax(arg, &tmp, 10);
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tmpmax = strtoimax(arg, &tmp, 10);
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if(errno != 0 or tmp == arg or *tmp != '\0'
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or tmp_id != (gid_t)tmp_id){
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or tmpmax != (gid_t)tmpmax){
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argp_error(state, "Bad group ID number: \"%s\", using %"
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PRIdMAX, arg, (intmax_t)gid);
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case 132: /* --debug */
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case 133: /* --plugin-helper-dir */
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free(pluginhelperdir);
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pluginhelperdir = strdup(arg);
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if(pluginhelperdir != NULL){
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525
* These reproduce what we would get without ARGP_NO_HELP
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/* Work around Debian bug #633582:
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<https://bugs.debian.org/633582> */
811
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
812
if(plugindir_fd == -1){
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error(0, errno, "open(\"" PDIR "\")");
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ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
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error(0, errno, "fstat");
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if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
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ret = fchown(plugindir_fd, uid, gid);
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error(0, errno, "fchown");
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/* Lower permissions */
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/* Strip permissions down to nobody */
835
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error(0, errno, "setgid");
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ret = set_cloexec_flag(dir_fd);
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error(0, errno, "set_cloexec_flag");
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TEMP_FAILURE_RETRY(close(dir_fd));
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exitstatus = EX_OSERR;
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#endif /* O_CLOEXEC */
868
int good_name(const struct dirent * const dirent){
869
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
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"*.dpkg-old", "*.dpkg-bak",
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"*.dpkg-divert", NULL };
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#pragma GCC diagnostic push
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#pragma GCC diagnostic ignored "-Wcast-qual"
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for(const char **pat = (const char **)patterns;
877
*pat != NULL; pat++){
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#pragma GCC diagnostic pop
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if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
884
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
885
" matching pattern %s\n", dirent->d_name, *pat);
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dir = fdopendir(dir_fd);
794
error(0, errno, "Could not open plugin dir");
795
TEMP_FAILURE_RETRY(close(dir_fd));
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exitstatus = EX_OSERR;
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int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
895
if(numplugins == -1){
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error(0, errno, "Could not scan plugin dir");
898
exitstatus = EX_OSERR;
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FD_ZERO(&rfds_all);
904
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/* Read and execute any executable in the plugin directory*/
905
for(int i = 0; i < numplugins; i++){
907
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
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error(0, errno, "Could not open plugin");
806
dirst = readdir(dir);
807
} while(dirst == NULL and errno == EINTR);
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/* All directory entries have been processed */
812
error(0, errno, "readdir");
813
exitstatus = EX_IOERR;
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d_name_len = strlen(dirst->d_name);
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/* Ignore dotfiles, backup files and other junk */
823
bool bad_name = false;
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const char const *bad_prefixes[] = { ".", "#", NULL };
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const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
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".dpkg-divert", NULL };
831
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
832
size_t pre_len = strlen(*pre);
833
if((d_name_len >= pre_len)
834
and strncmp((dirst->d_name), *pre, pre_len) == 0){
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
837
" with bad prefix %s\n", dirst->d_name, *pre);
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for(const char **suf = bad_suffixes; *suf != NULL; suf++){
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size_t suf_len = strlen(*suf);
848
if((d_name_len >= suf_len)
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and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
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fprintf(stderr, "Ignoring plugin dir entry \"%s\""
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" with bad suffix %s\n", dirst->d_name, *suf);
866
if(plugindir == NULL){
867
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
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ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
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error(0, errno, "asprintf");
913
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
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ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
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error(0, errno, "stat");
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/* Ignore non-executable files */
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if(not S_ISREG(st.st_mode)
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or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
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or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
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fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
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" with bad type or mode\n",
928
plugindir != NULL ? plugindir : PDIR,
929
direntries[i]->d_name);
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
936
plugin *p = getplugin(direntries[i]->d_name);
897
plugin *p = getplugin(dirst->d_name);
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error(0, errno, "getplugin");
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905
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
946
direntries[i]->d_name);
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ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
982
#else /* O_CLOEXEC */
983
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
984
#endif /* O_CLOEXEC */
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942
error(0, errno, "pipe");
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943
exitstatus = EX_OSERR;
991
if(pipefd[0] >= FD_SETSIZE){
992
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
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exitstatus = EX_OSERR;
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/* Ask OS to automatic close the pipe on exec */
1002
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ret = set_cloexec_flag(pipefd[0]);
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error(0, errno, "set_cloexec_flag");
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exitstatus = EX_OSERR;
1008
free(direntries[i]);
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ret = set_cloexec_flag(pipefd[1]);
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error(0, errno, "set_cloexec_flag");
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exitstatus = EX_OSERR;
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free(direntries[i]);
1020
#endif /* not O_CLOEXEC */
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959
/* Block SIGCHLD until process is safely in process list */
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ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
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&sigchld_action.sa_mask,
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994
_exit(EX_OSERR);
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if(fexecve(plugin_fd, p->argv,
1066
(p->environ[0] != NULL) ? p->environ : environ) < 0){
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error(0, errno, "fexecve for %s/%s",
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plugindir != NULL ? plugindir : PDIR,
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direntries[i]->d_name);
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/* If dir has no file descriptor, we could not set FD_CLOEXEC
999
above and must now close it manually here. */
1002
if(p->environ[0] == NULL){
1003
if(execv(filename, p->argv) < 0){
1004
error(0, errno, "execv");
1008
if(execve(filename, p->argv, p->environ) < 0){
1009
error(0, errno, "execve");
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1013
/* no return */
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1015
/* Parent process */
1075
close(pipefd[1]); /* Close unused write end of pipe */
1077
plugin *new_plugin = getplugin(direntries[i]->d_name);
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TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1019
plugin *new_plugin = getplugin(dirst->d_name);
1078
1020
if(new_plugin == NULL){
1079
1021
error(0, errno, "getplugin");
1080
1022
ret = (int)(TEMP_FAILURE_RETRY
1210
1153
/* This process has not completed. Does it have any output? */
1211
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1154
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1212
1157
/* This process had nothing to say at this time */
1213
1158
proc = proc->next;
1216
1161
/* Before reading, make the process' data buffer large enough */
1217
1162
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1218
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1219
+ (size_t) BUFFER_SIZE);
1220
if(new_buffer == NULL){
1163
proc->buffer = realloc(proc->buffer, proc->buffer_size
1164
+ (size_t) BUFFER_SIZE);
1165
if(proc->buffer == NULL){
1221
1166
error(0, errno, "malloc");
1222
1167
exitstatus = EX_OSERR;
1225
proc->buffer = new_buffer;
1226
1170
proc->buffer_size += BUFFER_SIZE;
1228
1172
/* Read from the process */