/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- try_help
- check_stdout
- usage
- cleanup
- exiterr
- fatal
- perror_fatal
- check_child_status
- ck_fopen
- ck_fclose
- ck_fread
- ck_fwrite
- ck_fflush
- expand_name
- lf_init
- lf_refill
- lf_copy
- lf_skip
- lf_snarf
- main
- diffarg
- catchsig
- signal_handler
- trapsigs
- untrapsig
- checksigs
- give_help
- skip_white
- flush_line
- edit
- interact
- diraccess
- temporary_file
/* sdiff - side-by-side merge of file differences
Copyright (C) 1992-1996, 1998, 2001-2002, 2004, 2006-2007, 2009-2011 Free
Software Foundation, Inc.
This file is part of GNU DIFF.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "system.h"
#include "paths.h"
#include <stdio.h>
#include <unlocked-io.h>
#include <c-stack.h>
#include <dirname.h>
#include <error.h>
#include <exitfail.h>
#include <file-type.h>
#include <getopt.h>
#include <progname.h>
#include <sh-quote.h>
#include <version-etc.h>
#include <xalloc.h>
/* The official name of this program (e.g., no `g' prefix). */
#define PROGRAM_NAME "sdiff"
#define AUTHORS \
proper_name ("Thomas Lord")
/* Size of chunks read from files which must be parsed into lines. */
#define SDIFF_BUFSIZE ((size_t) 65536)
static char const *editor_program = DEFAULT_EDITOR_PROGRAM;
static char const **diffargv;
static char * volatile tmpname;
static FILE *tmp;
#if HAVE_WORKING_FORK
static pid_t volatile diffpid;
#endif
struct line_filter;
static void catchsig (int);
static bool edit (struct line_filter *, char const *, lin, lin, struct line_filter *, char const *, lin, lin, FILE *);
static bool interact (struct line_filter *, struct line_filter *, char const *, struct line_filter *, char const *, FILE *);
static void checksigs (void);
static void diffarg (char const *);
static void fatal (char const *) __attribute__((noreturn));
static void perror_fatal (char const *) __attribute__((noreturn));
static void trapsigs (void);
static void untrapsig (int);
#define NUM_SIGS (sizeof sigs / sizeof *sigs)
static int const sigs[] = {
#ifdef SIGHUP
SIGHUP,
#endif
#ifdef SIGQUIT
SIGQUIT,
#endif
#ifdef SIGTERM
SIGTERM,
#endif
#ifdef SIGXCPU
SIGXCPU,
#endif
#ifdef SIGXFSZ
SIGXFSZ,
#endif
#ifdef SIGPIPE
SIGPIPE,
#endif
SIGINT
#define handler_index_of_SIGINT (NUM_SIGS - 1)
};
#if HAVE_SIGACTION
/* Prefer `sigaction' if available, since `signal' can lose signals. */
static struct sigaction initial_action[NUM_SIGS];
# define initial_handler(i) (initial_action[i].sa_handler)
static void signal_handler (int, void (*) (int));
#else
static void (*initial_action[NUM_SIGS]) ();
# define initial_handler(i) (initial_action[i])
# define signal_handler(sig, handler) signal (sig, handler)
#endif
static bool diraccess (char const *);
static int temporary_file (void);
/* Options: */
/* Name of output file if -o specified. */
static char const *output;
/* Do not print common lines. */
static bool suppress_common_lines;
/* Value for the long option that does not have single-letter equivalents. */
enum
{
DIFF_PROGRAM_OPTION = CHAR_MAX + 1,
HELP_OPTION,
STRIP_TRAILING_CR_OPTION,
TABSIZE_OPTION
};
static struct option const longopts[] =
{
{"diff-program", 1, 0, DIFF_PROGRAM_OPTION},
{"expand-tabs", 0, 0, 't'},
{"help", 0, 0, HELP_OPTION},
{"ignore-all-space", 0, 0, 'W'}, /* swap W and w for historical reasons */
{"ignore-blank-lines", 0, 0, 'B'},
{"ignore-case", 0, 0, 'i'},
{"ignore-matching-lines", 1, 0, 'I'},
{"ignore-space-change", 0, 0, 'b'},
{"ignore-tab-expansion", 0, 0, 'E'},
{"ignore-trailing-space", 0, 0, 'Z'},
{"left-column", 0, 0, 'l'},
{"minimal", 0, 0, 'd'},
{"output", 1, 0, 'o'},
{"speed-large-files", 0, 0, 'H'},
{"strip-trailing-cr", 0, 0, STRIP_TRAILING_CR_OPTION},
{"suppress-common-lines", 0, 0, 's'},
{"tabsize", 1, 0, TABSIZE_OPTION},
{"text", 0, 0, 'a'},
{"version", 0, 0, 'v'},
{"width", 1, 0, 'w'},
{0, 0, 0, 0}
};
static void try_help (char const *, char const *) __attribute__((noreturn));
static void
try_help (char const *reason_msgid, char const *operand)
{
if (reason_msgid)
error (0, 0, _(reason_msgid), operand);
error (EXIT_TROUBLE, 0, _("Try `%s --help' for more information."),
program_name);
abort ();
}
static void
check_stdout (void)
{
if (ferror (stdout))
fatal ("write failed");
else if (fclose (stdout) != 0)
perror_fatal (_("standard output"));
}
static char const * const option_help_msgid[] = {
N_("-o, --output=FILE operate interactively, sending output to FILE"),
"",
N_("-i, --ignore-case consider upper- and lower-case to be the same"),
N_("-E, --ignore-tab-expansion ignore changes due to tab expansion"),
N_("-Z, --ignore-trailing-space ignore white space at line end"),
N_("-b, --ignore-space-change ignore changes in the amount of white space"),
N_("-W, --ignore-all-space ignore all white space"),
N_("-B, --ignore-blank-lines ignore changes whose lines are all blank"),
N_("-I, --ignore-matching-lines=RE ignore changes whose lines all match RE"),
N_(" --strip-trailing-cr strip trailing carriage return on input"),
N_("-a, --text treat all files as text"),
"",
N_("-w, --width=NUM output at most NUM (default 130) print columns"),
N_("-l, --left-column output only the left column of common lines"),
N_("-s, --suppress-common-lines do not output common lines"),
"",
N_("-t, --expand-tabs expand tabs to spaces in output"),
N_(" --tabsize=NUM tab stops at every NUM (default 8) print columns"),
"",
N_("-d, --minimal try hard to find a smaller set of changes"),
N_("-H, --speed-large-files assume large files, many scattered small changes"),
N_(" --diff-program=PROGRAM use PROGRAM to compare files"),
"",
N_(" --help display this help and exit"),
N_("-v, --version output version information and exit"),
0
};
static void
usage (void)
{
char const * const *p;
printf (_("Usage: %s [OPTION]... FILE1 FILE2\n"), program_name);
printf ("%s\n\n",
_("Side-by-side merge of differences between FILE1 and FILE2."));
fputs (_("\
Mandatory arguments to long options are mandatory for short options too.\n\
"), stdout);
for (p = option_help_msgid; *p; p++)
if (**p)
printf (" %s\n", _(*p));
else
putchar ('\n');
printf ("\n%s\n%s\n",
_("If a FILE is `-', read standard input."),
_("Exit status is 0 if inputs are the same, 1 if different, 2 if trouble."));
emit_bug_reporting_address ();
}
/* Clean up after a signal or other failure. This function is
async-signal-safe. */
static void
cleanup (int signo __attribute__((unused)))
{
#if HAVE_WORKING_FORK
if (0 < diffpid)
kill (diffpid, SIGPIPE);
#endif
if (tmpname)
unlink (tmpname);
}
static void exiterr (void) __attribute__((noreturn));
static void
exiterr (void)
{
cleanup (0);
untrapsig (0);
checksigs ();
exit (EXIT_TROUBLE);
}
static void
fatal (char const *msgid)
{
error (0, 0, "%s", _(msgid));
exiterr ();
}
static void
perror_fatal (char const *msg)
{
int e = errno;
checksigs ();
error (0, e, "%s", msg);
exiterr ();
}
static void
check_child_status (int werrno, int wstatus, int max_ok_status,
char const *subsidiary_program)
{
int status = (! werrno && WIFEXITED (wstatus)
? WEXITSTATUS (wstatus)
: INT_MAX);
if (max_ok_status < status)
{
error (0, werrno,
_(status == 126
? "subsidiary program `%s' could not be invoked"
: status == 127
? "subsidiary program `%s' not found"
: status == INT_MAX
? "subsidiary program `%s' failed"
: "subsidiary program `%s' failed (exit status %d)"),
subsidiary_program, status);
exiterr ();
}
}
static FILE *
ck_fopen (char const *fname, char const *type)
{
FILE *r = fopen (fname, type);
if (! r)
perror_fatal (fname);
return r;
}
static void
ck_fclose (FILE *f)
{
if (fclose (f))
perror_fatal ("fclose");
}
static size_t
ck_fread (char *buf, size_t size, FILE *f)
{
size_t r = fread (buf, sizeof (char), size, f);
if (r == 0 && ferror (f))
perror_fatal (_("read failed"));
return r;
}
static void
ck_fwrite (char const *buf, size_t size, FILE *f)
{
if (fwrite (buf, sizeof (char), size, f) != size)
perror_fatal (_("write failed"));
}
static void
ck_fflush (FILE *f)
{
if (fflush (f) != 0)
perror_fatal (_("write failed"));
}
static char const *
expand_name (char *name, bool is_dir, char const *other_name)
{
if (STREQ (name, "-"))
fatal ("cannot interactively merge standard input");
if (! is_dir)
return name;
else
{
/* Yield NAME/BASE, where BASE is OTHER_NAME's basename. */
char const *base = last_component (other_name);
size_t namelen = strlen (name), baselen = base_len (base);
bool insert_slash = *last_component (name) && name[namelen - 1] != '/';
char *r = xmalloc (namelen + insert_slash + baselen + 1);
memcpy (r, name, namelen);
r[namelen] = '/';
memcpy (r + namelen + insert_slash, base, baselen);
r[namelen + insert_slash + baselen] = '\0';
return r;
}
}
struct line_filter {
FILE *infile;
char *bufpos;
char *buffer;
char *buflim;
};
static void
lf_init (struct line_filter *lf, FILE *infile)
{
lf->infile = infile;
lf->bufpos = lf->buffer = lf->buflim = xmalloc (SDIFF_BUFSIZE + 1);
lf->buflim[0] = '\n';
}
/* Fill an exhausted line_filter buffer from its INFILE */
static size_t
lf_refill (struct line_filter *lf)
{
size_t s = ck_fread (lf->buffer, SDIFF_BUFSIZE, lf->infile);
lf->bufpos = lf->buffer;
lf->buflim = lf->buffer + s;
lf->buflim[0] = '\n';
checksigs ();
return s;
}
/* Advance LINES on LF's infile, copying lines to OUTFILE */
static void
lf_copy (struct line_filter *lf, lin lines, FILE *outfile)
{
char *start = lf->bufpos;
while (lines)
{
lf->bufpos = (char *) memchr (lf->bufpos, '\n', lf->buflim - lf->bufpos);
if (! lf->bufpos)
{
ck_fwrite (start, lf->buflim - start, outfile);
if (! lf_refill (lf))
return;
start = lf->bufpos;
}
else
{
--lines;
++lf->bufpos;
}
}
ck_fwrite (start, lf->bufpos - start, outfile);
}
/* Advance LINES on LF's infile without doing output */
static void
lf_skip (struct line_filter *lf, lin lines)
{
while (lines)
{
lf->bufpos = (char *) memchr (lf->bufpos, '\n', lf->buflim - lf->bufpos);
if (! lf->bufpos)
{
if (! lf_refill (lf))
break;
}
else
{
--lines;
++lf->bufpos;
}
}
}
/* Snarf a line into a buffer. Return EOF if EOF, 0 if error, 1 if OK. */
static int
lf_snarf (struct line_filter *lf, char *buffer, size_t bufsize)
{
for (;;)
{
char *start = lf->bufpos;
char *next = (char *) memchr (start, '\n', lf->buflim + 1 - start);
size_t s = next - start;
if (bufsize <= s)
return 0;
memcpy (buffer, start, s);
if (next < lf->buflim)
{
buffer[s] = 0;
lf->bufpos = next + 1;
return 1;
}
if (! lf_refill (lf))
return s ? 0 : EOF;
buffer += s;
bufsize -= s;
}
}
int
main (int argc, char *argv[])
{
int opt;
char const *prog;
exit_failure = EXIT_TROUBLE;
initialize_main (&argc, &argv);
set_program_name (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
c_stack_action (cleanup);
prog = getenv ("EDITOR");
if (prog)
editor_program = prog;
diffarg (DEFAULT_DIFF_PROGRAM);
/* parse command line args */
while ((opt = getopt_long (argc, argv, "abBdEHiI:lo:stvw:WZ", longopts, 0))
!= -1)
{
switch (opt)
{
case 'a':
diffarg ("-a");
break;
case 'b':
diffarg ("-b");
break;
case 'B':
diffarg ("-B");
break;
case 'd':
diffarg ("-d");
break;
case 'E':
diffarg ("-E");
break;
case 'H':
diffarg ("-H");
break;
case 'i':
diffarg ("-i");
break;
case 'I':
diffarg ("-I");
diffarg (optarg);
break;
case 'l':
diffarg ("--left-column");
break;
case 'o':
output = optarg;
break;
case 's':
suppress_common_lines = true;
break;
case 't':
diffarg ("-t");
break;
case 'v':
version_etc (stdout, PROGRAM_NAME, PACKAGE_NAME, Version,
AUTHORS, (char *) NULL);
check_stdout ();
return EXIT_SUCCESS;
case 'w':
diffarg ("-W");
diffarg (optarg);
break;
case 'W':
diffarg ("-w");
break;
case 'Z':
diffarg ("-Z");
break;
case DIFF_PROGRAM_OPTION:
diffargv[0] = optarg;
break;
case HELP_OPTION:
usage ();
check_stdout ();
return EXIT_SUCCESS;
case STRIP_TRAILING_CR_OPTION:
diffarg ("--strip-trailing-cr");
break;
case TABSIZE_OPTION:
diffarg ("--tabsize");
diffarg (optarg);
break;
default:
try_help (0, 0);
}
}
if (argc - optind != 2)
{
if (argc - optind < 2)
try_help ("missing operand after `%s'", argv[argc - 1]);
else
try_help ("extra operand `%s'", argv[optind + 2]);
}
if (! output)
{
/* easy case: diff does everything for us */
if (suppress_common_lines)
diffarg ("--suppress-common-lines");
diffarg ("-y");
diffarg ("--");
diffarg (argv[optind]);
diffarg (argv[optind + 1]);
diffarg (0);
execvp (diffargv[0], (char **) diffargv);
perror_fatal (diffargv[0]);
}
else
{
char const *lname, *rname;
FILE *left, *right, *out, *diffout;
bool interact_ok;
struct line_filter lfilt;
struct line_filter rfilt;
struct line_filter diff_filt;
bool leftdir = diraccess (argv[optind]);
bool rightdir = diraccess (argv[optind + 1]);
if (leftdir & rightdir)
fatal ("both files to be compared are directories");
lname = expand_name (argv[optind], leftdir, argv[optind + 1]);
left = ck_fopen (lname, "r");
rname = expand_name (argv[optind + 1], rightdir, argv[optind]);
right = ck_fopen (rname, "r");
out = ck_fopen (output, "w");
diffarg ("--sdiff-merge-assist");
diffarg ("--");
diffarg (argv[optind]);
diffarg (argv[optind + 1]);
diffarg (0);
trapsigs ();
#if ! HAVE_WORKING_FORK
{
size_t cmdsize = 1;
char *p, *command;
int i;
for (i = 0; diffargv[i]; i++)
cmdsize += shell_quote_length (diffargv[i]) + 1;
command = p = xmalloc (cmdsize);
for (i = 0; diffargv[i]; i++)
{
p = shell_quote_copy (p, diffargv[i]);
*p++ = ' ';
}
p[-1] = 0;
errno = 0;
diffout = popen (command, "r");
if (! diffout)
perror_fatal (command);
free (command);
}
#else
{
int diff_fds[2];
if (pipe (diff_fds) != 0)
perror_fatal ("pipe");
diffpid = fork ();
if (diffpid < 0)
perror_fatal ("fork");
if (! diffpid)
{
/* Alter the child's SIGINT and SIGPIPE handlers;
this may munge the parent.
The child ignores SIGINT in case the user interrupts the editor.
The child does not ignore SIGPIPE, even if the parent does. */
if (initial_handler (handler_index_of_SIGINT) != SIG_IGN)
signal_handler (SIGINT, SIG_IGN);
signal_handler (SIGPIPE, SIG_DFL);
close (diff_fds[0]);
if (diff_fds[1] != STDOUT_FILENO)
{
dup2 (diff_fds[1], STDOUT_FILENO);
close (diff_fds[1]);
}
execvp (diffargv[0], (char **) diffargv);
_exit (errno == ENOENT ? 127 : 126);
}
close (diff_fds[1]);
diffout = fdopen (diff_fds[0], "r");
if (! diffout)
perror_fatal ("fdopen");
}
#endif
lf_init (&diff_filt, diffout);
lf_init (&lfilt, left);
lf_init (&rfilt, right);
interact_ok = interact (&diff_filt, &lfilt, lname, &rfilt, rname, out);
ck_fclose (left);
ck_fclose (right);
ck_fclose (out);
{
int wstatus;
int werrno = 0;
#if ! HAVE_WORKING_FORK
wstatus = pclose (diffout);
if (wstatus == -1)
werrno = errno;
#else
ck_fclose (diffout);
while (waitpid (diffpid, &wstatus, 0) < 0)
if (errno == EINTR)
checksigs ();
else
perror_fatal ("waitpid");
diffpid = 0;
#endif
if (tmpname)
{
unlink (tmpname);
tmpname = 0;
}
if (! interact_ok)
exiterr ();
check_child_status (werrno, wstatus, EXIT_FAILURE, diffargv[0]);
untrapsig (0);
checksigs ();
exit (WEXITSTATUS (wstatus));
}
}
return EXIT_SUCCESS; /* Fool `-Wall'. */
}
static void
diffarg (char const *a)
{
static size_t diffargs, diffarglim;
if (diffargs == diffarglim)
{
if (! diffarglim)
diffarglim = 16;
else if (PTRDIFF_MAX / (2 * sizeof *diffargv) <= diffarglim)
xalloc_die ();
else
diffarglim *= 2;
diffargv = xrealloc (diffargv, diffarglim * sizeof *diffargv);
}
diffargv[diffargs++] = a;
}
/* Signal handling */
static bool volatile ignore_SIGINT;
static int volatile signal_received;
static bool sigs_trapped;
static void
catchsig (int s)
{
#if ! HAVE_SIGACTION
signal (s, SIG_IGN);
#endif
if (! (s == SIGINT && ignore_SIGINT))
signal_received = s;
}
#if HAVE_SIGACTION
static struct sigaction catchaction;
static void
signal_handler (int sig, void (*handler) (int))
{
catchaction.sa_handler = handler;
sigaction (sig, &catchaction, 0);
}
#endif
static void
trapsigs (void)
{
int i;
#if HAVE_SIGACTION
catchaction.sa_flags = SA_RESTART;
sigemptyset (&catchaction.sa_mask);
for (i = 0; i < NUM_SIGS; i++)
sigaddset (&catchaction.sa_mask, sigs[i]);
#endif
for (i = 0; i < NUM_SIGS; i++)
{
#if HAVE_SIGACTION
sigaction (sigs[i], 0, &initial_action[i]);
#else
initial_action[i] = signal (sigs[i], SIG_IGN);
#endif
if (initial_handler (i) != SIG_IGN)
signal_handler (sigs[i], catchsig);
}
#ifdef SIGCHLD
/* System V fork+wait does not work if SIGCHLD is ignored. */
signal (SIGCHLD, SIG_DFL);
#endif
sigs_trapped = true;
}
/* Untrap signal S, or all trapped signals if S is zero. */
static void
untrapsig (int s)
{
int i;
if (sigs_trapped)
for (i = 0; i < NUM_SIGS; i++)
if ((! s || sigs[i] == s) && initial_handler (i) != SIG_IGN)
{
#if HAVE_SIGACTION
sigaction (sigs[i], &initial_action[i], 0);
#else
signal (sigs[i], initial_action[i]);
#endif
}
}
/* Exit if a signal has been received. */
static void
checksigs (void)
{
int s = signal_received;
if (s)
{
cleanup (0);
/* Yield an exit status indicating that a signal was received. */
untrapsig (s);
kill (getpid (), s);
/* That didn't work, so exit with error status. */
exit (EXIT_TROUBLE);
}
}
static void
give_help (void)
{
fprintf (stderr, "%s", _("\
ed:\tEdit then use both versions, each decorated with a header.\n\
eb:\tEdit then use both versions.\n\
el or e1:\tEdit then use the left version.\n\
er or e2:\tEdit then use the right version.\n\
e:\tDiscard both versions then edit a new one.\n\
l or 1:\tUse the left version.\n\
r or 2:\tUse the right version.\n\
s:\tSilently include common lines.\n\
v:\tVerbosely include common lines.\n\
q:\tQuit.\n\
"));
}
static int
skip_white (void)
{
int c;
for (;;)
{
c = getchar ();
if (! isspace (c) || c == '\n')
break;
checksigs ();
}
if (ferror (stdin))
perror_fatal (_("read failed"));
return c;
}
static void
flush_line (void)
{
int c;
while ((c = getchar ()) != '\n' && c != EOF)
continue;
if (ferror (stdin))
perror_fatal (_("read failed"));
}
/* interpret an edit command */
static bool
edit (struct line_filter *left, char const *lname, lin lline, lin llen,
struct line_filter *right, char const *rname, lin rline, lin rlen,
FILE *outfile)
{
for (;;)
{
int cmd0 IF_LINT (= 0);
int cmd1 IF_LINT (= 0);
bool gotcmd = false;
while (! gotcmd)
{
if (putchar ('%') != '%')
perror_fatal (_("write failed"));
ck_fflush (stdout);
cmd0 = skip_white ();
switch (cmd0)
{
case '1': case '2': case 'l': case 'r':
case 's': case 'v': case 'q':
if (skip_white () != '\n')
{
give_help ();
flush_line ();
continue;
}
gotcmd = true;
break;
case 'e':
cmd1 = skip_white ();
switch (cmd1)
{
case '1': case '2': case 'b': case 'd': case 'l': case 'r':
if (skip_white () != '\n')
{
give_help ();
flush_line ();
continue;
}
gotcmd = true;
break;
case '\n':
gotcmd = true;
break;
default:
give_help ();
flush_line ();
continue;
}
break;
case EOF:
if (feof (stdin))
{
gotcmd = true;
cmd0 = 'q';
break;
}
/* Fall through. */
default:
flush_line ();
/* Fall through. */
case '\n':
give_help ();
continue;
}
}
switch (cmd0)
{
case '1': case 'l':
lf_copy (left, llen, outfile);
lf_skip (right, rlen);
return true;
case '2': case 'r':
lf_copy (right, rlen, outfile);
lf_skip (left, llen);
return true;
case 's':
suppress_common_lines = true;
break;
case 'v':
suppress_common_lines = false;
break;
case 'q':
return false;
case 'e':
{
int fd;
if (tmpname)
tmp = fopen (tmpname, "w");
else
{
if ((fd = temporary_file ()) < 0)
perror_fatal ("mkstemp");
tmp = fdopen (fd, "w");
}
if (! tmp)
perror_fatal (tmpname);
switch (cmd1)
{
case 'd':
if (llen)
{
if (llen == 1)
fprintf (tmp, "--- %s %ld\n", lname, (long int) lline);
else
fprintf (tmp, "--- %s %ld,%ld\n", lname,
(long int) lline,
(long int) (lline + llen - 1));
}
/* Fall through. */
case '1': case 'b': case 'l':
lf_copy (left, llen, tmp);
break;
default:
lf_skip (left, llen);
break;
}
switch (cmd1)
{
case 'd':
if (rlen)
{
if (rlen == 1)
fprintf (tmp, "+++ %s %ld\n", rname, (long int) rline);
else
fprintf (tmp, "+++ %s %ld,%ld\n", rname,
(long int) rline,
(long int) (rline + rlen - 1));
}
/* Fall through. */
case '2': case 'b': case 'r':
lf_copy (right, rlen, tmp);
break;
default:
lf_skip (right, rlen);
break;
}
ck_fclose (tmp);
{
int wstatus;
int werrno = 0;
ignore_SIGINT = true;
checksigs ();
{
#if ! HAVE_WORKING_FORK
char *command =
xmalloc (shell_quote_length (editor_program)
+ 1 + strlen (tmpname) + 1);
sprintf (shell_quote_copy (command, editor_program),
" %s", tmpname);
wstatus = system (command);
if (wstatus == -1)
werrno = errno;
free (command);
#else
pid_t pid;
pid = fork ();
if (pid == 0)
{
char const *argv[3];
int i = 0;
argv[i++] = editor_program;
argv[i++] = tmpname;
argv[i] = 0;
execvp (editor_program, (char **) argv);
_exit (errno == ENOENT ? 127 : 126);
}
if (pid < 0)
perror_fatal ("fork");
while (waitpid (pid, &wstatus, 0) < 0)
if (errno == EINTR)
checksigs ();
else
perror_fatal ("waitpid");
#endif
}
ignore_SIGINT = false;
check_child_status (werrno, wstatus, EXIT_SUCCESS,
editor_program);
}
{
char buf[SDIFF_BUFSIZE];
size_t size;
tmp = ck_fopen (tmpname, "r");
while ((size = ck_fread (buf, SDIFF_BUFSIZE, tmp)) != 0)
{
checksigs ();
ck_fwrite (buf, size, outfile);
}
ck_fclose (tmp);
}
return true;
}
default:
give_help ();
break;
}
}
}
/* Alternately reveal bursts of diff output and handle user commands. */
static bool
interact (struct line_filter *diff,
struct line_filter *left, char const *lname,
struct line_filter *right, char const *rname,
FILE *outfile)
{
lin lline = 1, rline = 1;
for (;;)
{
char diff_help[256];
int snarfed = lf_snarf (diff, diff_help, sizeof diff_help);
if (snarfed <= 0)
return snarfed != 0;
checksigs ();
if (diff_help[0] == ' ')
puts (diff_help + 1);
else
{
char *numend;
uintmax_t val;
lin llen, rlen, lenmax;
errno = 0;
llen = val = strtoumax (diff_help + 1, &numend, 10);
if (llen < 0 || llen != val || errno || *numend != ',')
fatal (diff_help);
rlen = val = strtoumax (numend + 1, &numend, 10);
if (rlen < 0 || rlen != val || errno || *numend)
fatal (diff_help);
lenmax = MAX (llen, rlen);
switch (diff_help[0])
{
case 'i':
if (suppress_common_lines)
lf_skip (diff, lenmax);
else
lf_copy (diff, lenmax, stdout);
lf_copy (left, llen, outfile);
lf_skip (right, rlen);
break;
case 'c':
lf_copy (diff, lenmax, stdout);
if (! edit (left, lname, lline, llen,
right, rname, rline, rlen,
outfile))
return false;
break;
default:
fatal (diff_help);
}
lline += llen;
rline += rlen;
}
}
}
/* Return true if DIR is an existing directory. */
static bool
diraccess (char const *dir)
{
struct stat buf;
return stat (dir, &buf) == 0 && S_ISDIR (buf.st_mode);
}
#ifndef P_tmpdir
# define P_tmpdir "/tmp"
#endif
#ifndef TMPDIR_ENV
# define TMPDIR_ENV "TMPDIR"
#endif
/* Open a temporary file and return its file descriptor. Put into
tmpname the address of a newly allocated buffer that holds the
file's name. Use the prefix "sdiff". */
static int
temporary_file (void)
{
char const *tmpdir = getenv (TMPDIR_ENV);
char const *dir = tmpdir ? tmpdir : P_tmpdir;
char *buf = xmalloc (strlen (dir) + 1 + 5 + 6 + 1);
int fd;
int e;
sigset_t procmask;
sigset_t blocked;
sprintf (buf, "%s/sdiffXXXXXX", dir);
sigemptyset (&blocked);
sigaddset (&blocked, SIGINT);
sigprocmask (SIG_BLOCK, &blocked, &procmask);
fd = mkstemp (buf);
e = errno;
if (0 <= fd)
tmpname = buf;
sigprocmask (SIG_SETMASK, &procmask, 0);
errno = e;
return fd;
}