/* sysopen style args, i.e. integer mode and permissions */
STRLEN ix = 0;
if (num_svs != 0) {
- Perl_croak(aTHX_ "panic:sysopen with multiple args");
+ Perl_croak(aTHX_ "panic: sysopen with multiple args");
}
+ if (rawmode & (O_WRONLY|O_RDWR|O_CREAT
+#ifdef O_APPEND /* Not fully portable. */
+ |O_APPEND
+#endif
+#ifdef O_TRUNC /* Not fully portable. */
+ |O_TRUNC
+#endif
+ ))
+ TAINT_PROPER("sysopen");
mode[ix++] = '#'; /* Marker to openn to use numeric "sysopen" */
#if defined(USE_64_BIT_RAWIO) && defined(O_LARGEFILE)
- rawmode |= O_LARGEFILE;
-#endif
-
-#ifndef O_ACCMODE
-#define O_ACCMODE 3 /* Assume traditional implementation */
+ rawmode |= O_LARGEFILE; /* Transparently largefiley. */
#endif
- switch (result = rawmode & O_ACCMODE) {
- case O_RDONLY:
- IoTYPE(io) = IoTYPE_RDONLY;
- break;
- case O_WRONLY:
- IoTYPE(io) = IoTYPE_WRONLY;
- break;
- case O_RDWR:
- default:
- IoTYPE(io) = IoTYPE_RDWR;
- break;
- }
- writing = (result > 0);
-
- if (result == O_RDONLY) {
- mode[ix++] = 'r';
- }
-#ifdef O_APPEND
- else if (rawmode & O_APPEND) {
- mode[ix++] = 'a';
- if (result != O_WRONLY)
- mode[ix++] = '+';
- }
-#endif
- else {
- if (result == O_WRONLY)
- mode[ix++] = 'w';
- else {
- mode[ix++] = 'r';
- mode[ix++] = '+';
- }
- }
- if (rawmode & O_BINARY)
- mode[ix++] = 'b';
- mode[ix] = '\0';
+ IoTYPE(io) = PerlIO_intmode2str(rawmode, &mode[ix], &writing);
namesv = sv_2mortal(newSVpvn(name,strlen(name)));
num_svs = 1;
svp = &namesv;
type = Nullch;
- fp = PerlIO_openn(aTHX_ type,mode, -1, rawmode, rawperm, NULL, num_svs, svp);
+ fp = PerlIO_openn(aTHX_ type, mode, -1, rawmode, rawperm, NULL, num_svs, svp);
}
else {
/* Regular (non-sys) open */
STRLEN olen = len;
char *tend;
int dodup = 0;
+ PerlIO *that_fp = NULL;
type = savepvn(name, len);
tend = type+len;
SAVEFREEPV(type);
- /* Loose trailing white space */
- while (tend > type && isSPACE(tend[-1]))
- *tend-- = '\0';
+
+ /* Lose leading and trailing white space */
+ /*SUPPRESS 530*/
+ for (; isSPACE(*type); type++) ;
+ while (tend > type && isSPACE(tend[-1]))
+ *--tend = '\0';
+
if (num_svs) {
/* New style explict name, type is just mode and discipline/layer info */
STRLEN l = 0;
- name = SvOK(*svp) && (*svp != &PL_sv_undef) ? SvPV(*svp, l) : "";
+ name = SvOK(*svp) ? SvPV(*svp, l) : "";
len = (I32)l;
name = savepvn(name, len);
SAVEFREEPV(name);
- /*SUPPRESS 530*/
- for (; isSPACE(*type); type++) ;
}
else {
name = type;
len = tend-type;
}
IoTYPE(io) = *type;
- if ((*type == IoTYPE_RDWR) && ((!num_svs || tend > type+1 && tend[-1] != IoTYPE_PIPE))) { /* scary */
+ if ((*type == IoTYPE_RDWR) && /* scary */
+ (*(type+1) == IoTYPE_RDONLY || *(type+1) == IoTYPE_WRONLY) &&
+ ((!num_svs || (tend > type+1 && tend[-1] != IoTYPE_PIPE)))) {
+ TAINT_PROPER("open");
mode[1] = *type++;
writing = 1;
}
if (*type == '&') {
duplicity:
- dodup = 1;
+ dodup = PERLIO_DUP_FD;
type++;
if (*type == '=') {
dodup = 0;
#endif
goto say_false;
}
- if (IoIFP(thatio)) {
- PerlIO *fp = IoIFP(thatio);
+ if ((that_fp = IoIFP(thatio))) {
/* Flush stdio buffer before dup. --mjd
* Unfortunately SEEK_CURing 0 seems to
* be optimized away on most platforms;
/* sfio fails to clear error on next
sfwrite, contrary to documentation.
-- Nick Clark */
- if (PerlIO_seek(fp, 0, SEEK_CUR) == -1)
- PerlIO_clearerr(fp);
+ if (PerlIO_seek(that_fp, 0, SEEK_CUR) == -1)
+ PerlIO_clearerr(that_fp);
#endif
/* On the other hand, do all platforms
* take gracefully to flushing a read-only
* filehandle? Perhaps we should do
* fsetpos(src)+fgetpos(dst)? --nik */
- PerlIO_flush(fp);
- fd = PerlIO_fileno(fp);
+ PerlIO_flush(that_fp);
+ fd = PerlIO_fileno(that_fp);
/* When dup()ing STDIN, STDOUT or STDERR
* explicitly set appropriate access mode */
- if (IoIFP(thatio) == PerlIO_stdout()
- || IoIFP(thatio) == PerlIO_stderr())
+ if (that_fp == PerlIO_stdout()
+ || that_fp == PerlIO_stderr())
IoTYPE(io) = IoTYPE_WRONLY;
- else if (IoIFP(thatio) == PerlIO_stdin())
+ else if (that_fp == PerlIO_stdin())
IoTYPE(io) = IoTYPE_RDONLY;
/* When dup()ing a socket, say result is
* one as well */
else
fd = -1;
}
- if (dodup)
- fd = PerlLIO_dup(fd);
- else
- was_fdopen = TRUE;
if (!num_svs)
type = Nullch;
- if (!(fp = PerlIO_openn(aTHX_ type,mode,fd,0,0,NULL,num_svs,svp))) {
+ if (that_fp) {
+ fp = PerlIO_fdupopen(aTHX_ that_fp, NULL, dodup);
+ }
+ else {
if (dodup)
- PerlLIO_close(fd);
+ fd = PerlLIO_dup(fd);
+ else
+ was_fdopen = TRUE;
+ if (!(fp = PerlIO_openn(aTHX_ type,mode,fd,0,0,NULL,num_svs,svp))) {
+ if (dodup)
+ PerlLIO_close(fd);
+ }
}
}
} /* & */
else {
- if (num_svs > 1) {
- Perl_croak(aTHX_ "More than one argument to '>' open");
- }
/*SUPPRESS 530*/
for (; isSPACE(*type); type++) ;
if (*type == IoTYPE_STD && (!type[1] || isSPACE(type[1]) || type[1] == ':')) {
type++;
fp = PerlIO_stdout();
IoTYPE(io) = IoTYPE_STD;
+ if (num_svs > 1) {
+ Perl_croak(aTHX_ "More than one argument to '>%c' open",IoTYPE_STD);
+ }
}
else {
if (!num_svs) {
} /* !& */
}
else if (*type == IoTYPE_RDONLY) {
- if (num_svs > 1) {
- Perl_croak(aTHX_ "More than one argument to '<' open");
- }
/*SUPPRESS 530*/
for (type++; isSPACE(*type); type++) ;
mode[0] = 'r';
type++;
fp = PerlIO_stdin();
IoTYPE(io) = IoTYPE_STD;
+ if (num_svs > 1) {
+ Perl_croak(aTHX_ "More than one argument to '<%c' open",IoTYPE_STD);
+ }
}
else {
if (!num_svs) {
if (ckWARN(WARN_IO)) {
if ((IoTYPE(io) == IoTYPE_RDONLY) &&
(fp == PerlIO_stdout() || fp == PerlIO_stderr())) {
- Perl_warner(aTHX_ WARN_IO, "'std%s' opened only for input",
- (fp == PerlIO_stdout()) ? "out" : "err");
+ Perl_warner(aTHX_ WARN_IO,
+ "Filehandle STD%s opened only for input",
+ (fp == PerlIO_stdout()) ? "OUT" : "ERR");
}
else if ((IoTYPE(io) == IoTYPE_WRONLY) && fp == PerlIO_stdin()) {
- Perl_warner(aTHX_ WARN_IO, "'stdin' opened only for output");
+ Perl_warner(aTHX_ WARN_IO,
+ "Filehandle STDIN opened only for output");
}
}
- if (IoTYPE(io) && IoTYPE(io) != IoTYPE_PIPE && IoTYPE(io) != IoTYPE_STD &&
- /* FIXME: This next term is a hack to avoid fileno on PerlIO::Scalar */
- !(num_svs && SvROK(*svp))) {
- if (PerlLIO_fstat(PerlIO_fileno(fp),&PL_statbuf) < 0) {
- (void)PerlIO_close(fp);
+ fd = PerlIO_fileno(fp);
+ /* If there is no fd (e.g. PerlIO::Scalar) assume it isn't a
+ * socket - this covers PerlIO::Scalar - otherwise unless we "know" the
+ * type probe for socket-ness.
+ */
+ if (IoTYPE(io) && IoTYPE(io) != IoTYPE_PIPE && IoTYPE(io) != IoTYPE_STD && fd >= 0) {
+ if (PerlLIO_fstat(fd,&PL_statbuf) < 0) {
+ /* If PerlIO claims to have fd we had better be able to fstat() it. */
+ (void) PerlIO_close(fp);
goto say_false;
}
+#ifndef PERL_MICRO
if (S_ISSOCK(PL_statbuf.st_mode))
IoTYPE(io) = IoTYPE_SOCKET; /* in case a socket was passed in to us */
#ifdef HAS_SOCKET
&& IoTYPE(io) != IoTYPE_WRONLY /* Dups of STD* filehandles already have */
&& IoTYPE(io) != IoTYPE_RDONLY /* type so they aren't marked as sockets */
) { /* on OS's that return 0 on fstat()ed pipe */
- char tmpbuf[256];
- Sock_size_t buflen = sizeof tmpbuf;
- if (PerlSock_getsockname(PerlIO_fileno(fp), (struct sockaddr *)tmpbuf,
- &buflen) >= 0
- || errno != ENOTSOCK)
- IoTYPE(io) = IoTYPE_SOCKET; /* some OS's return 0 on fstat()ed socket */
- /* but some return 0 for streams too, sigh */
- }
-#endif
+ char tmpbuf[256];
+ Sock_size_t buflen = sizeof tmpbuf;
+ if (PerlSock_getsockname(fd, (struct sockaddr *)tmpbuf, &buflen) >= 0
+ || errno != ENOTSOCK)
+ IoTYPE(io) = IoTYPE_SOCKET; /* some OS's return 0 on fstat()ed socket */
+ /* but some return 0 for streams too, sigh */
+ }
+#endif /* HAS_SOCKET */
+#endif /* !PERL_MICRO */
}
+
+ /* Eeek - FIXME !!!
+ * If this is a standard handle we discard all the layer stuff
+ * and just dup the fd into whatever was on the handle before !
+ */
+
if (saveifp) { /* must use old fp? */
/* If fd is less that PL_maxsysfd i.e. STDIN..STDERR
then dup the new fileno down
*/
- fd = PerlIO_fileno(fp);
if (saveofp) {
PerlIO_flush(saveofp); /* emulate PerlIO_close() */
if (saveofp != saveifp) { /* was a socket? */
if (savefd != fd) {
Pid_t pid;
SV *sv;
- PerlLIO_dup2(fd, savefd);
+ /* Still a small can-of-worms here if (say) PerlIO::Scalar
+ is assigned to (say) STDOUT - for now let dup2() fail
+ and provide the error
+ */
+ if (PerlLIO_dup2(fd, savefd) < 0) {
+ (void)PerlIO_close(fp);
+ goto say_false;
+ }
#ifdef VMS
if (savefd != PerlIO_fileno(PerlIO_stdin())) {
char newname[FILENAME_MAX+1];
- if (fgetname(fp, newname)) {
- if (savefd == PerlIO_fileno(PerlIO_stdout())) Perl_vmssetuserlnm("SYS$OUTPUT", newname);
- if (savefd == PerlIO_fileno(PerlIO_stderr())) Perl_vmssetuserlnm("SYS$ERROR", newname);
+ if (PerlIO_getname(fp, newname)) {
+ if (fd == PerlIO_fileno(PerlIO_stdout())) Perl_vmssetuserlnm(aTHX_ "SYS$OUTPUT", newname);
+ if (fd == PerlIO_fileno(PerlIO_stderr())) Perl_vmssetuserlnm(aTHX_ "SYS$ERROR", newname);
}
}
#endif
UNLOCK_FDPID_MUTEX;
(void)SvUPGRADE(sv, SVt_IV);
SvIVX(sv) = pid;
- if (!was_fdopen)
+ if (!was_fdopen) {
PerlIO_close(fp);
+ }
}
fp = saveifp;
PerlIO_clearerr(fp);
+ fd = PerlIO_fileno(fp);
}
#if defined(HAS_FCNTL) && defined(F_SETFD)
- {
+ if (fd >= 0) {
int save_errno = errno;
- fd = PerlIO_fileno(fp);
fcntl(fd,F_SETFD,fd > PL_maxsysfd); /* can change errno */
errno = save_errno;
}
IoFLAGS(io) &= ~IOf_NOLINE;
if (writing) {
if (IoTYPE(io) == IoTYPE_SOCKET
- || (IoTYPE(io) == IoTYPE_WRONLY && S_ISCHR(PL_statbuf.st_mode)) ) {
+ || (IoTYPE(io) == IoTYPE_WRONLY && fd >= 0 && S_ISCHR(PL_statbuf.st_mode)) ) {
mode[0] = 'w';
- if (!(IoOFP(io) = PerlIO_openn(aTHX_ type,mode,PerlIO_fileno(fp),0,0,NULL,num_svs,svp))) {
+ if (!(IoOFP(io) = PerlIO_openn(aTHX_ type,mode,fd,0,0,NULL,num_svs,svp))) {
PerlIO_close(fp);
IoIFP(io) = Nullfp;
goto say_false;
sv_catpv(sv,PL_inplace);
}
#ifndef FLEXFILENAMES
- if (PerlLIO_stat(SvPVX(sv),&PL_statbuf) >= 0
- && PL_statbuf.st_dev == filedev
- && PL_statbuf.st_ino == fileino
+ if ((PerlLIO_stat(SvPVX(sv),&PL_statbuf) >= 0
+ && PL_statbuf.st_dev == filedev
+ && PL_statbuf.st_ino == fileino)
#ifdef DJGPP
- || (_djstat_fail_bits & _STFAIL_TRUENAME)!=0
+ || ((_djstat_fail_bits & _STFAIL_TRUENAME)!=0)
#endif
)
{
if (!io)
return TRUE;
else if (ckWARN(WARN_IO) && (IoTYPE(io) == IoTYPE_WRONLY))
- {
- /* integrate to report_evil_fh()? */
- char *name = NULL;
- if (isGV(gv)) {
- SV* sv = sv_newmortal();
- gv_efullname4(sv, gv, Nullch, FALSE);
- name = SvPV_nolen(sv);
- }
- if (name && *name)
- Perl_warner(aTHX_ WARN_IO,
- "Filehandle %s opened only for output", name);
- else
- Perl_warner(aTHX_ WARN_IO,
- "Filehandle opened only for output");
- }
+ report_evil_fh(gv, io, OP_phoney_OUTPUT_ONLY);
while (IoIFP(io)) {
Off_t
Perl_do_tell(pTHX_ GV *gv)
{
- register IO *io;
+ register IO *io = 0;
register PerlIO *fp;
if (gv && (io = GvIO(gv)) && (fp = IoIFP(io))) {
bool
Perl_do_seek(pTHX_ GV *gv, Off_t pos, int whence)
{
- register IO *io;
+ register IO *io = 0;
register PerlIO *fp;
if (gv && (io = GvIO(gv)) && (fp = IoIFP(io))) {
Off_t
Perl_do_sysseek(pTHX_ GV *gv, Off_t pos, int whence)
{
- register IO *io;
+ register IO *io = 0;
register PerlIO *fp;
if (gv && (io = GvIO(gv)) && (fp = IoIFP(io)))
/* The old body of this is now in non-LAYER part of perlio.c
* This is a stub for any XS code which might have been calling it.
*/
- char *name = (O_BINARY != O_TEXT && !(mode & O_BINARY)) ? ":crlf" : ":raw";
+ char *name = ":raw";
+#ifdef PERLIO_USING_CRLF
+ if (!(mode & O_BINARY))
+ name = ":crlf";
+#endif
return PerlIO_binmode(aTHX_ fp, iotype, mode, name);
}
if (!SvUTF8(sv))
sv_utf8_upgrade(sv = sv_mortalcopy(sv));
}
- else if (DO_UTF8(sv))
- sv_utf8_downgrade((sv = sv_mortalcopy(sv)), FALSE);
+ else if (DO_UTF8(sv)) {
+ if (!sv_utf8_downgrade((sv = sv_mortalcopy(sv)), TRUE)
+ && ckWARN(WARN_UTF8))
+ {
+ Perl_warner(aTHX_ WARN_UTF8, "Wide character in print");
+ }
+ }
tmps = SvPV(sv, len);
break;
}
Perl_croak(aTHX_ "exec? I'm not *that* kind of operating system");
#else
register char **a;
- char *tmps;
+ char *tmps = Nullch;
STRLEN n_a;
if (sp > mark) {
{
register char **a;
register char *s;
- char flags[10];
while (*cmd && isSPACE(*cmd))
cmd++;
/* save an extra exec if possible */
#ifdef CSH
- if (strnEQ(cmd,PL_cshname,PL_cshlen) && strnEQ(cmd+PL_cshlen," -c",3)) {
- strcpy(flags,"-c");
- s = cmd+PL_cshlen+3;
- if (*s == 'f') {
- s++;
- strcat(flags,"f");
- }
- if (*s == ' ')
- s++;
- if (*s++ == '\'') {
- char *ncmd = s;
-
- while (*s)
- s++;
- if (s[-1] == '\n')
- *--s = '\0';
- if (s[-1] == '\'') {
- *--s = '\0';
- PerlProc_execl(PL_cshname,"csh", flags,ncmd,(char*)0);
- *s = '\'';
- return FALSE;
- }
+ {
+ char flags[10];
+ if (strnEQ(cmd,PL_cshname,PL_cshlen) &&
+ strnEQ(cmd+PL_cshlen," -c",3)) {
+ strcpy(flags,"-c");
+ s = cmd+PL_cshlen+3;
+ if (*s == 'f') {
+ s++;
+ strcat(flags,"f");
+ }
+ if (*s == ' ')
+ s++;
+ if (*s++ == '\'') {
+ char *ncmd = s;
+
+ while (*s)
+ s++;
+ if (s[-1] == '\n')
+ *--s = '\0';
+ if (s[-1] == '\'') {
+ *--s = '\0';
+ PerlProc_execl(PL_cshname,"csh", flags, ncmd, (char*)0);
+ *s = '\'';
+ return FALSE;
+ }
+ }
}
}
#endif /* CSH */
goto doshell;
for (s = cmd; *s; s++) {
- if (*s != ' ' && !isALPHA(*s) && strchr("$&*(){}[]'\";\\|?<>~`\n",*s)) {
+ if (*s != ' ' && !isALPHA(*s) &&
+ strchr("$&*(){}[]'\";\\|?<>~`\n",*s)) {
if (*s == '\n' && !s[1]) {
*s = '\0';
break;
} utbuf;
#endif
+ SV* accessed = *++mark;
+ SV* modified = *++mark;
+ void * utbufp = &utbuf;
+
+ /* be like C, and if both times are undefined, let the C
+ library figure out what to do. This usually means
+ "current time" */
+
+ if ( accessed == &PL_sv_undef && modified == &PL_sv_undef )
+ utbufp = NULL;
+
Zero(&utbuf, sizeof utbuf, char);
#ifdef BIG_TIME
- utbuf.actime = (Time_t)SvNVx(*++mark); /* time accessed */
- utbuf.modtime = (Time_t)SvNVx(*++mark); /* time modified */
+ utbuf.actime = (Time_t)SvNVx(accessed); /* time accessed */
+ utbuf.modtime = (Time_t)SvNVx(modified); /* time modified */
#else
- utbuf.actime = (Time_t)SvIVx(*++mark); /* time accessed */
- utbuf.modtime = (Time_t)SvIVx(*++mark); /* time modified */
+ utbuf.actime = (Time_t)SvIVx(accessed); /* time accessed */
+ utbuf.modtime = (Time_t)SvIVx(modified); /* time modified */
#endif
APPLY_TAINT_PROPER();
tot = sp - mark;
while (++mark <= sp) {
char *name = SvPVx(*mark, n_a);
APPLY_TAINT_PROPER();
- if (PerlLIO_utime(name, &utbuf))
+ if (PerlLIO_utime(name, utbufp))
tot--;
}
}
id = SvIVx(*++mark);
opstr = *++mark;
opbuf = SvPV(opstr, opsize);
- if (opsize < sizeof(struct sembuf)
- || (opsize % sizeof(struct sembuf)) != 0) {
+ if (opsize < 3 * SHORTSIZE
+ || (opsize % (3 * SHORTSIZE))) {
SETERRNO(EINVAL,LIB$_INVARG);
return -1;
}
SETERRNO(0,0);
- return semop(id, (struct sembuf *)opbuf, opsize/sizeof(struct sembuf));
+ /* We can't assume that sizeof(struct sembuf) == 3 * sizeof(short). */
+ {
+ int nsops = opsize / (3 * sizeof (short));
+ int i = nsops;
+ short *ops = (short *) opbuf;
+ short *o = ops;
+ struct sembuf *temps, *t;
+ I32 result;
+
+ New (0, temps, nsops, struct sembuf);
+ t = temps;
+ while (i--) {
+ t->sem_num = *o++;
+ t->sem_op = *o++;
+ t->sem_flg = *o++;
+ t++;
+ }
+ result = semop(id, temps, nsops);
+ t = temps;
+ o = ops;
+ i = nsops;
+ while (i--) {
+ *o++ = t->sem_num;
+ *o++ = t->sem_op;
+ *o++ = t->sem_flg;
+ t++;
+ }
+ Safefree(temps);
+ return result;
+ }
#else
Perl_croak(aTHX_ "semop not implemented");
#endif
#endif /* SYSV IPC */
/*
+=head1 IO Functions
+
=for apidoc start_glob
Function called by C<do_readline> to spawn a glob (or do the glob inside
perl on VMS). This code used to be inline, but now perl uses C<File::Glob>
-this glob starter is only used by miniperl during the build proccess.
+this glob starter is only used by miniperl during the build process.
Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up.
=cut
char rslt[NAM$C_MAXRSS+1+sizeof(unsigned short int)] = {'\0','\0'};
char vmsspec[NAM$C_MAXRSS+1];
char *rstr = rslt + sizeof(unsigned short int), *begin, *end, *cp;
- char tmpfnam[L_tmpnam] = "SYS$SCRATCH:";
$DESCRIPTOR(dfltdsc,"SYS$DISK:[]*.*;");
PerlIO *tmpfp;
STRLEN i;
((struct NAM *)((struct FAB *)cxt)->fab$l_nam)->nam$l_fnb
but that's unsupported, so I don't want to do it now and
have it bite someone in the future. */
- strcat(tmpfnam,PerlLIO_tmpnam(NULL));
cp = SvPV(tmpglob,i);
for (; i; i--) {
if (cp[i] == ';') hasver = 1;
break;
}
}
- if ((tmpfp = PerlIO_open(tmpfnam,"w+","fop=dlt")) != NULL) {
+ if ((tmpfp = PerlIO_tmpfile()) != NULL) {
Stat_t st;
if (!PerlLIO_stat(SvPVX(tmpglob),&st) && S_ISDIR(st.st_mode))
ok = ((wilddsc.dsc$a_pointer = tovmspath(SvPVX(tmpglob),vmsspec)) != NULL);
else ok = ((wilddsc.dsc$a_pointer = tovmsspec(SvPVX(tmpglob),vmsspec)) != NULL);
if (ok) wilddsc.dsc$w_length = (unsigned short int) strlen(wilddsc.dsc$a_pointer);
+ for (cp=wilddsc.dsc$a_pointer; ok && cp && *cp; cp++)
+ if (*cp == '?') *cp = '%'; /* VMS style single-char wildcard */
while (ok && ((sts = lib$find_file(&wilddsc,&rsdsc,&cxt,
&dfltdsc,NULL,NULL,NULL))&1)) {
end = rstr + (unsigned long int) *rslt;
https://perl5.git.perl.org / perl5.git / blobdiff