31
7
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
32
8
#include <iso646.h> /* and, or, not*/
33
9
#include <errno.h> /* errno, EINTR */
35
10
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
37
12
#include <stddef.h> /* NULL */
38
13
#include <string.h> /* strlen(), memcmp() */
39
#include <stdio.h> /* asprintf()*/
14
#include <stdio.h> /* asprintf(), perror() */
40
15
#include <unistd.h> /* close(), write(), readlink(),
41
16
read(), STDOUT_FILENO, sleep(),
42
17
fork(), setuid(), geteuid(),
43
18
setsid(), chdir(), dup2(),
44
19
STDERR_FILENO, execv() */
45
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
46
EXIT_SUCCESS, malloc(), _exit(),
20
#include <stdlib.h> /* free(), EXIT_FAILURE, strtoul(),
21
realloc(), EXIT_SUCCESS, malloc(),
23
#include <stdlib.h> /* getenv() */
48
24
#include <dirent.h> /* opendir(), readdir(), closedir() */
49
#include <inttypes.h> /* intmax_t, strtoimax() */
50
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#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
51
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
53
27
sig_atomic_t interrupted_by_signal = 0;
55
const char usplash_name[] = "/sbin/usplash";
57
static void termination_handler(int signum){
58
if(interrupted_by_signal){
29
static void termination_handler(__attribute__((unused))int signum){
61
30
interrupted_by_signal = 1;
62
signal_received = signum;
65
static bool usplash_write(int *fifo_fd_r,
66
const char *cmd, const char *arg){
33
static bool usplash_write(const char *cmd, const char *arg){
68
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
69
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
35
* usplash_write("TIMEOUT", "15") will write "TIMEOUT 15\0"
36
* usplash_write("PULSATE", NULL) will write "PULSATE\0"
75
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
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fifo_fd = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
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if(fifo_fd == -1 and (errno != EINTR or interrupted_by_signal)){
47
}while(fifo_fd == -1);
82
49
const char *cmd_line;
83
50
size_t cmd_line_len;
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51
char *cmd_line_alloc = NULL;
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cmd_line_len = strlen(cmd) + 1;
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cmd_line_len = strlen(cmd);
90
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ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
58
if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
93
TEMP_FAILURE_RETRY(close(*fifo_fd_r));
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65
cmd_line = cmd_line_alloc;
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66
cmd_line_len = (size_t)ret + 1;
102
69
size_t written = 0;
104
while(written < cmd_line_len){
105
sret = write(*fifo_fd_r, cmd_line + written,
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cmd_line_len - written);
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TEMP_FAILURE_RETRY(close(*fifo_fd_r));
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free(cmd_line_alloc);
70
while(not interrupted_by_signal and written < cmd_line_len){
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ret = write(fifo_fd, cmd_line + written,
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cmd_line_len - written);
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if(errno != EINTR or interrupted_by_signal){
114
written += (size_t)sret;
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written += (size_t)ret;
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free(cmd_line_alloc);
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if(ret == -1 and (errno != EINTR or interrupted_by_signal)){
93
if(interrupted_by_signal){
121
/* Create prompt string */
122
char *makeprompt(void){
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const char *const cryptsource = getenv("cryptsource");
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const char *const crypttarget = getenv("crypttarget");
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const char prompt_start[] = "Enter passphrase to unlock the disk";
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if(cryptsource == NULL){
130
if(crypttarget == NULL){
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ret = asprintf(&prompt, "%s: ", prompt_start);
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ret = asprintf(&prompt, "%s (%s): ", prompt_start,
137
if(crypttarget == NULL){
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ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
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ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
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cryptsource, crypttarget);
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pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
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int main(__attribute__((unused))int argc,
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__attribute__((unused))char **argv){
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bool an_error_occured = false;
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/* Create prompt string */
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const char *const cryptsource = getenv("cryptsource");
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const char *const crypttarget = getenv("crypttarget");
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const char prompt_start[] = "Enter passphrase to unlock the disk";
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if(cryptsource == NULL){
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if(crypttarget == NULL){
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ret = asprintf(&prompt, "%s: ", prompt_start);
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ret = asprintf(&prompt, "%s (%s): ", prompt_start,
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if(crypttarget == NULL){
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ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
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ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
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cryptsource, crypttarget);
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/* Find usplash process */
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pid_t usplash_pid = 0;
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char *cmdline = NULL;
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size_t cmdline_len = 0;
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DIR *proc_dir = opendir("/proc");
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if(proc_dir == NULL){
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error(0, errno, "opendir");
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for(struct dirent *proc_ent = readdir(proc_dir);
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proc_ent = readdir(proc_dir)){
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tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
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if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
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or tmpmax != (pid_t)tmpmax){
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const char usplash_name[] = "/sbin/usplash";
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DIR *proc_dir = opendir("/proc");
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if(proc_dir == NULL){
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for(struct dirent *proc_ent = readdir(proc_dir);
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proc_ent = readdir(proc_dir)){
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pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
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/* Not a process */
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/* Find the executable name by doing readlink() on the
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/proc/<pid>/exe link */
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char exe_target[sizeof(usplash_name)];
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/* create file name string */
183
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
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error(0, errno, "asprintf");
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goto fail_find_usplash;
189
/* Check that it refers to a symlink owned by root:root */
190
struct stat exe_stat;
191
ret = lstat(exe_link, &exe_stat);
197
error(0, errno, "lstat");
199
goto fail_find_usplash;
201
if(not S_ISLNK(exe_stat.st_mode)
202
or exe_stat.st_uid != 0
203
or exe_stat.st_gid != 0){
208
sret = readlink(exe_link, exe_target, sizeof(exe_target));
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/* Compare executable name */
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if((sret != ((ssize_t)sizeof(exe_target)-1))
213
or (memcmp(usplash_name, exe_target,
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sizeof(exe_target)-1) != 0)){
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/* Read and save the command line of usplash in "cmdline" */
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/* Open /proc/<pid>/cmdline */
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/* Find the executable name by doing readlink() on the
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/proc/<pid>/exe link */
154
char exe_target[sizeof(usplash_name)];
224
char *cmdline_filename;
225
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
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error(0, errno, "asprintf");
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goto fail_find_usplash;
231
cl_fd = open(cmdline_filename, O_RDONLY);
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free(cmdline_filename);
234
error(0, errno, "open");
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goto fail_find_usplash;
156
/* create file name string */
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ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
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/* Check that it refers to a symlink owned by root:root */
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struct stat exe_stat;
168
ret = lstat(exe_link, &exe_stat);
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if(not S_ISLNK(exe_stat.st_mode)
177
or exe_stat.st_uid != 0
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or exe_stat.st_gid != 0){
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sret = readlink(exe_link, exe_target, sizeof(exe_target));
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size_t cmdline_allocated = 0;
240
const size_t blocksize = 1024;
242
/* Allocate more space? */
243
if(cmdline_len + blocksize > cmdline_allocated){
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tmp = realloc(cmdline, cmdline_allocated + blocksize);
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error(0, errno, "realloc");
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goto fail_find_usplash;
189
if((sret == ((ssize_t)sizeof(exe_target)-1))
190
and (memcmp(usplash_name, exe_target,
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sizeof(exe_target)-1) == 0)){
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/* Read and save the command line of usplash in "cmdline" */
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/* Open /proc/<pid>/cmdline */
198
char *cmdline_filename;
199
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
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cl_fd = open(cmdline_filename, O_RDONLY);
210
free(cmdline_filename);
215
free(cmdline_filename);
251
cmdline_allocated += blocksize;
254
sret = read(cl_fd, cmdline + cmdline_len,
255
cmdline_allocated - cmdline_len);
257
error(0, errno, "read");
217
size_t cmdline_allocated = 0;
219
const size_t blocksize = 1024;
221
if(cmdline_len + blocksize > cmdline_allocated){
222
tmp = realloc(cmdline, cmdline_allocated + blocksize);
231
cmdline_allocated += blocksize;
233
sret = read(cl_fd, cmdline + cmdline_len,
234
cmdline_allocated - cmdline_len);
242
cmdline_len += (size_t)sret;
259
goto fail_find_usplash;
261
cmdline_len += (size_t)sret;
265
error(0, errno, "close");
266
goto fail_find_usplash;
269
/* Close directory */
270
ret = closedir(proc_dir);
272
error(0, errno, "closedir");
273
goto fail_find_usplash;
276
*cmdline_r = cmdline;
277
*cmdline_len_r = cmdline_len;
284
if(proc_dir != NULL){
286
249
closedir(proc_dir);
292
int main(__attribute__((unused))int argc,
293
__attribute__((unused))char **argv){
300
pid_t usplash_pid = -1;
301
bool usplash_accessed = false;
302
int status = EXIT_FAILURE; /* Default failure exit status */
304
char *prompt = makeprompt();
310
/* Find usplash process */
311
char *cmdline = NULL;
312
size_t cmdline_len = 0;
313
usplash_pid = find_usplash(&cmdline, &cmdline_len);
314
251
if(usplash_pid == 0){
315
status = EX_UNAVAILABLE;
319
256
/* Set up the signal handler */
322
259
new_action = { .sa_handler = termination_handler,
324
261
sigemptyset(&new_action.sa_mask);
325
ret = sigaddset(&new_action.sa_mask, SIGINT);
327
error(0, errno, "sigaddset");
331
ret = sigaddset(&new_action.sa_mask, SIGHUP);
333
error(0, errno, "sigaddset");
337
ret = sigaddset(&new_action.sa_mask, SIGTERM);
339
error(0, errno, "sigaddset");
262
sigaddset(&new_action.sa_mask, SIGINT);
263
sigaddset(&new_action.sa_mask, SIGHUP);
264
sigaddset(&new_action.sa_mask, SIGTERM);
343
265
ret = sigaction(SIGINT, NULL, &old_action);
346
error(0, errno, "sigaction");
351
271
if(old_action.sa_handler != SIG_IGN){
352
272
ret = sigaction(SIGINT, &new_action, NULL);
355
error(0, errno, "sigaction");
361
279
ret = sigaction(SIGHUP, NULL, &old_action);
364
error(0, errno, "sigaction");
369
285
if(old_action.sa_handler != SIG_IGN){
370
286
ret = sigaction(SIGHUP, &new_action, NULL);
373
error(0, errno, "sigaction");
379
293
ret = sigaction(SIGTERM, NULL, &old_action);
382
error(0, errno, "sigaction");
387
299
if(old_action.sa_handler != SIG_IGN){
388
300
ret = sigaction(SIGTERM, &new_action, NULL);
391
error(0, errno, "sigaction");
399
usplash_accessed = true;
400
309
/* Write command to FIFO */
401
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
403
error(0, errno, "usplash_write");
409
if(interrupted_by_signal){
413
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
415
error(0, errno, "usplash_write");
421
if(interrupted_by_signal){
428
/* Read reply from usplash */
430
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
431
if(outfifo_fd == -1){
433
error(0, errno, "open");
439
if(interrupted_by_signal){
444
size_t buf_allocated = 0;
445
const size_t blocksize = 1024;
447
/* Allocate more space */
448
if(buf_len + blocksize > buf_allocated){
449
char *tmp = realloc(buf, buf_allocated + blocksize);
452
error(0, errno, "realloc");
458
buf_allocated += blocksize;
460
sret = read(outfifo_fd, buf + buf_len,
461
buf_allocated - buf_len);
464
error(0, errno, "read");
467
TEMP_FAILURE_RETRY(close(outfifo_fd));
470
if(interrupted_by_signal){
474
buf_len += (size_t)sret;
476
ret = close(outfifo_fd);
479
error(0, errno, "close");
486
if(interrupted_by_signal){
490
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
492
error(0, errno, "usplash_write");
498
if(interrupted_by_signal){
502
ret = close(fifo_fd);
505
error(0, errno, "close");
512
/* Print password to stdout */
514
while(written < buf_len){
516
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
519
error(0, errno, "write");
526
if(interrupted_by_signal){
529
written += (size_t)sret;
534
if(interrupted_by_signal){
547
/* If usplash was never accessed, we can stop now */
548
if(not usplash_accessed){
554
ret = (int)TEMP_FAILURE_RETRY(close(fifo_fd));
555
if(ret == -1 and errno != EINTR){
556
error(0, errno, "close");
561
/* Close output FIFO */
562
if(outfifo_fd != -1){
563
ret = (int)TEMP_FAILURE_RETRY(close(outfifo_fd));
565
error(0, errno, "close");
310
if(not interrupted_by_signal){
311
if(not usplash_write("TIMEOUT", "0")
312
and (errno != EINTR)){
313
perror("usplash_write");
314
an_error_occured = true;
317
if(not interrupted_by_signal and not an_error_occured){
318
if(not usplash_write("INPUTQUIET", prompt)
319
and (errno != EINTR)){
320
perror("usplash_write");
321
an_error_occured = true;
326
/* This is not really a loop; while() is used to be able to "break"
327
out of it; those breaks are marked "Big" */
328
while(not interrupted_by_signal and not an_error_occured){
335
fifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
339
an_error_occured = true;
342
if(interrupted_by_signal){
346
}while(fifo_fd == -1);
347
if(interrupted_by_signal or an_error_occured){
352
size_t buf_allocated = 0;
353
const size_t blocksize = 1024;
355
if(buf_len + blocksize > buf_allocated){
356
char *tmp = realloc(buf, buf_allocated + blocksize);
359
an_error_occured = true;
363
buf_allocated += blocksize;
366
sret = read(fifo_fd, buf + buf_len, buf_allocated - buf_len);
370
an_error_occured = true;
373
if(interrupted_by_signal){
378
if(interrupted_by_signal or an_error_occured){
382
buf_len += (size_t)sret;
385
if(interrupted_by_signal or an_error_occured){
389
if(not usplash_write("TIMEOUT", "15")
390
and (errno != EINTR)){
391
perror("usplash_write");
392
an_error_occured = true;
394
if(interrupted_by_signal or an_error_occured){
398
/* Print password to stdout */
400
while(written < buf_len){
402
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
406
an_error_occured = true;
409
if(interrupted_by_signal){
414
if(interrupted_by_signal or an_error_occured){
417
written += (size_t)sret;
420
if(not interrupted_by_signal and not an_error_occured){
425
} /* end of non-loop while() */
427
/* If we got here, an error or interrupt must have happened */
569
429
/* Create argc and argv for new usplash*/
570
430
int cmdline_argc = 0;