pax, tar, and cpio are one binary that changes behavior based on the last
component of argv[0]. Lots of shared code, so sure, but I find the
strcmp() tests in the main code overly complex and perhaps an affront to
clear style. (It's _not_ really a perf issue, as in per-file processing
it only checks this for directories and not each file or block.)
So how about we have a enum for the mode that gets set when it decides how
to parse the options and is then checked directly after that? Is this
clearer?
Philip Guenther
Index: extern.h
===================================================================
RCS file: /cvs/src/bin/pax/extern.h,v
retrieving revision 1.55
diff -u -p -r1.55 extern.h
--- extern.h 14 Aug 2016 04:47:52 -0000 1.55
+++ extern.h 23 Aug 2016 03:49:10 -0000
@@ -240,6 +240,7 @@ extern int exit_val;
extern int docrc;
extern char *dirptr;
extern char *argv0;
+extern enum op_mode { OP_PAX, OP_TAR, OP_CPIO } op_mode;
extern FILE *listf;
extern int listfd;
extern char *tempfile;
Index: pax.c
===================================================================
RCS file: /cvs/src/bin/pax/pax.c,v
retrieving revision 1.45
diff -u -p -r1.45 pax.c
--- pax.c 23 Jun 2016 06:37:36 -0000 1.45
+++ pax.c 23 Aug 2016 03:49:10 -0000
@@ -90,6 +90,7 @@ int exit_val; /* exit value */
int docrc; /* check/create file crc */
char *dirptr; /* destination dir in a copy */
char *argv0; /* root of argv[0] */
+enum op_mode op_mode; /* what program are we acting as? */
sigset_t s_mask; /* signal mask for cleanup critical sect */
FILE *listf = stderr; /* file pointer to print file list to */
int listfd = STDERR_FILENO; /* fd matching listf, for sighandler output */
Index: options.c
===================================================================
RCS file: /cvs/src/bin/pax/options.c,v
retrieving revision 1.94
diff -u -p -r1.94 options.c
--- options.c 14 Aug 2016 04:47:52 -0000 1.94
+++ options.c 23 Aug 2016 03:49:10 -0000
@@ -186,11 +186,13 @@ options(int argc, char **argv)
argv0 = __progname;
if (strcmp(NM_TAR, argv0) == 0) {
+ op_mode = OP_TAR;
tar_options(argc, argv);
return;
}
#ifndef NOCPIO
else if (strcmp(NM_CPIO, argv0) == 0) {
+ op_mode = OP_CPIO;
cpio_options(argc, argv);
return;
}
@@ -199,6 +201,7 @@ options(int argc, char **argv)
* assume pax as the default
*/
argv0 = NM_PAX;
+ op_mode = OP_PAX;
pax_options(argc, argv);
}
Index: ar_io.c
===================================================================
RCS file: /cvs/src/bin/pax/ar_io.c,v
retrieving revision 1.57
diff -u -p -r1.57 ar_io.c
--- ar_io.c 14 Aug 2016 18:30:33 -0000 1.57
+++ ar_io.c 23 Aug 2016 03:49:10 -0000
@@ -390,12 +390,12 @@ ar_close(int in_sig)
return;
}
- if (strcmp(NM_PAX, argv0) == 0)
+ if (op_mode == OP_PAX)
(void)dprintf(listfd, "%s: %s vol %d, %lu files,"
" %llu bytes read, %llu bytes written.\n",
argv0, frmt->name, arvol-1, flcnt, rdcnt, wrcnt);
#ifndef NOCPIO
- else if (strcmp(NM_CPIO, argv0) == 0)
+ else if (op_mode == OP_CPIO)
(void)dprintf(listfd, "%llu blocks\n",
(rdcnt ? rdcnt : wrcnt) / 5120);
#endif /* !NOCPIO */
@@ -1112,7 +1112,7 @@ ar_next(void)
if (sigprocmask(SIG_SETMASK, &o_mask, NULL) < 0)
syswarn(0, errno, "Unable to restore signal mask");
- if (done || !wr_trail || force_one_volume || strcmp(NM_TAR, argv0) == 0)
+ if (done || !wr_trail || force_one_volume || op_mode == OP_TAR)
return(-1);
tty_prnt("\nATTENTION! %s archive volume change required.\n", argv0);
Index: file_subs.c
===================================================================
RCS file: /cvs/src/bin/pax/file_subs.c,v
retrieving revision 1.50
diff -u -p -r1.50 file_subs.c
--- file_subs.c 23 Aug 2016 03:31:44 -0000 1.50
+++ file_subs.c 23 Aug 2016 03:49:10 -0000
@@ -371,7 +371,7 @@ node_creat(ARCHD *arcn)
* potential symlink chain before trying to create the
* directory.
*/
- if (strcmp(NM_TAR, argv0) == 0 && Lflag) {
+ if (op_mode == OP_TAR && Lflag) {
while (lstat(nm, &sb) == 0 &&
S_ISLNK(sb.st_mode)) {
len = readlink(nm, target,
@@ -484,7 +484,7 @@ badlink:
if (pmode && !defer_pmode)
set_pmode(nm, arcn->sb.st_mode);
- if (arcn->type == PAX_DIR && strcmp(NM_CPIO, argv0) != 0) {
+ if (arcn->type == PAX_DIR && op_mode != OP_CPIO) {
/*
* Dirs must be processed again at end of extract to set times
* and modes to agree with those stored in the archive. However
@@ -758,7 +758,7 @@ set_ids(char *fnm, uid_t uid, gid_t gid)
* ignore EPERM unless in verbose mode or being run by root.
* if running as pax, POSIX requires a warning.
*/
- if (strcmp(NM_PAX, argv0) == 0 || errno != EPERM || vflag ||
+ if (op_mode == OP_PAX || errno != EPERM || vflag ||
geteuid() == 0)
syswarn(1, errno, "Unable to set file uid/gid of %s",
fnm);
@@ -775,7 +775,7 @@ fset_ids(char *fnm, int fd, uid_t uid, g
* ignore EPERM unless in verbose mode or being run by root.
* if running as pax, POSIX requires a warning.
*/
- if (strcmp(NM_PAX, argv0) == 0 || errno != EPERM || vflag ||
+ if (op_mode == OP_PAX || errno != EPERM || vflag ||
geteuid() == 0)
syswarn(1, errno, "Unable to set file uid/gid of %s",
fnm);
