19
19
* along with this program. If not, see
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20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
22
* Contact the authors at <mandos@recompile.se>.
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#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
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 */
33
#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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stderr, STDOUT_FILENO, fclose() */
33
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
34
WIFEXITED(), WEXITSTATUS(), wait(),
35
pid_t, uid_t, gid_t, getuid(),
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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, stat(), S_ISREG() */
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#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
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#include <iso646.h> /* and, or, not */
45
#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(),
52
execv(), write(), read(),
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#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(),
49
faccessat() pipe2(), fork(),
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_exit(), dup2(), fexecve(), read()
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
56
#include <string.h> /* strsep, strlen(), asprintf(),
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strsignal(), strcmp(), strncmp() */
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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 <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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519
case 128: /* --plugin-dir */
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plugindir = strdup(arg);
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if(plugindir != NULL){
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526
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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tmpmax = strtoimax(arg, &tmp, 10);
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tmp_id = strtoimax(arg, &tmp, 10);
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if(errno != 0 or tmp == arg or *tmp != '\0'
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or tmpmax != (uid_t)tmpmax){
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or tmp_id != (uid_t)tmp_id){
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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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540
case 131: /* --groupid */
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tmpmax = strtoimax(arg, &tmp, 10);
541
tmp_id = strtoimax(arg, &tmp, 10);
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if(errno != 0 or tmp == arg or *tmp != '\0'
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or tmpmax != (gid_t)tmpmax){
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or tmp_id != (gid_t)tmp_id){
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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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* These reproduce what we would get without ARGP_NO_HELP
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/* Strip permissions down to nobody */
811
/* Work around Debian bug #633582:
812
<http://bugs.debian.org/633582> */
813
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
814
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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TEMP_FAILURE_RETRY(close(plugindir_fd));
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/* Lower permissions */
748
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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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867
#endif /* O_CLOEXEC */
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dir = fdopendir(dir_fd);
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error(0, errno, "Could not open plugin dir");
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TEMP_FAILURE_RETRY(close(dir_fd));
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exitstatus = EX_OSERR;
870
int good_name(const struct dirent * const dirent){
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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;
879
*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)
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fprintf(stderr, "Ignoring plugin dir entry \"%s\""
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" matching pattern %s\n", dirent->d_name, *pat);
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#if __GLIBC_PREREQ(2, 15)
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int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
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#else /* not __GLIBC_PREREQ(2, 15) */
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int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
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&direntries, good_name, alphasort);
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#endif /* not __GLIBC_PREREQ(2, 15) */
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#else /* not __GLIBC__ */
904
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
905
&direntries, good_name, alphasort);
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#endif /* not __GLIBC__ */
907
if(numplugins == -1){
908
error(0, errno, "Could not scan plugin dir");
910
exitstatus = EX_OSERR;
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914
FD_ZERO(&rfds_all);
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/* Read and execute any executable in the plugin directory*/
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;
819
d_name_len = strlen(dirst->d_name);
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/* Ignore dotfiles, backup files and other junk */
823
bool bad_name = false;
825
const char const *bad_prefixes[] = { ".", "#", NULL };
827
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
830
".dpkg-divert", NULL };
831
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
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size_t pre_len = strlen(*pre);
833
if((d_name_len >= pre_len)
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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++){
847
size_t suf_len = strlen(*suf);
848
if((d_name_len >= suf_len)
849
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
852
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
853
" with bad suffix %s\n", dirst->d_name, *suf);
866
if(plugindir == NULL){
867
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
870
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
875
error(0, errno, "asprintf");
917
for(int i = 0; i < numplugins; i++){
919
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
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error(0, errno, "Could not open plugin");
879
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
925
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
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error(0, errno, "stat");
928
TEMP_FAILURE_RETRY(close(plugin_fd));
886
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/* Ignore non-executable files */
887
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if(not S_ISREG(st.st_mode)
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or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
935
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
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fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
939
" with bad type or mode\n",
940
plugindir != NULL ? plugindir : PDIR,
941
direntries[i]->d_name);
943
TEMP_FAILURE_RETRY(close(plugin_fd));
897
plugin *p = getplugin(dirst->d_name);
948
plugin *p = getplugin(direntries[i]->d_name);
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error(0, errno, "getplugin");
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TEMP_FAILURE_RETRY(close(plugin_fd));
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fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
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direntries[i]->d_name);
960
TEMP_FAILURE_RETRY(close(plugin_fd));
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993
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
994
#else /* O_CLOEXEC */
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ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
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#endif /* O_CLOEXEC */
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error(0, errno, "pipe");
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exitstatus = EX_OSERR;
1000
free(direntries[i]);
1003
if(pipefd[0] >= FD_SETSIZE){
1004
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1006
TEMP_FAILURE_RETRY(close(pipefd[0]));
1007
TEMP_FAILURE_RETRY(close(pipefd[1]));
1008
exitstatus = EX_OSERR;
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free(direntries[i]);
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1013
/* Ask OS to automatic close the pipe on exec */
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1014
ret = set_cloexec_flag(pipefd[0]);
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error(0, errno, "set_cloexec_flag");
1017
TEMP_FAILURE_RETRY(close(pipefd[0]));
1018
TEMP_FAILURE_RETRY(close(pipefd[1]));
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1019
exitstatus = EX_OSERR;
1020
free(direntries[i]);
953
1023
ret = set_cloexec_flag(pipefd[1]);
955
1025
error(0, errno, "set_cloexec_flag");
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TEMP_FAILURE_RETRY(close(pipefd[0]));
1027
TEMP_FAILURE_RETRY(close(pipefd[1]));
956
1028
exitstatus = EX_OSERR;
1029
free(direntries[i]);
1032
#endif /* not O_CLOEXEC */
959
1033
/* Block SIGCHLD until process is safely in process list */
960
1034
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
961
1035
&sigchld_action.sa_mask,
994
1074
_exit(EX_OSERR);
998
/* 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");
1077
if(fexecve(plugin_fd, p->argv,
1078
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1079
error(0, errno, "fexecve for %s/%s",
1080
plugindir != NULL ? plugindir : PDIR,
1081
direntries[i]->d_name);
1013
1084
/* no return */
1015
1086
/* Parent process */
1016
1087
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1019
plugin *new_plugin = getplugin(dirst->d_name);
1089
TEMP_FAILURE_RETRY(close(plugin_fd));
1090
plugin *new_plugin = getplugin(direntries[i]->d_name);
1020
1091
if(new_plugin == NULL){
1021
1092
error(0, errno, "getplugin");
1022
1093
ret = (int)(TEMP_FAILURE_RETRY
1153
1252
/* This process has not completed. Does it have any output? */
1253
#if defined (__GNUC__) and defined (__GLIBC__)
1254
#if not __GLIBC_PREREQ(2, 16)
1255
#pragma GCC diagnostic push
1256
#pragma GCC diagnostic ignored "-Wsign-conversion"
1154
1259
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1265
#if defined (__GNUC__) and defined (__GLIBC__)
1266
#if not __GLIBC_PREREQ(2, 16)
1267
#pragma GCC diagnostic pop
1157
1270
/* This process had nothing to say at this time */
1158
1271
proc = proc->next;
1161
1274
/* Before reading, make the process' data buffer large enough */
1162
1275
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1163
proc->buffer = realloc(proc->buffer, proc->buffer_size
1164
+ (size_t) BUFFER_SIZE);
1165
if(proc->buffer == NULL){
1276
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1277
+ (size_t) BUFFER_SIZE);
1278
if(new_buffer == NULL){
1166
1279
error(0, errno, "malloc");
1167
1280
exitstatus = EX_OSERR;
1283
proc->buffer = new_buffer;
1170
1284
proc->buffer_size += BUFFER_SIZE;
1172
1286
/* Read from the process */