/* $Id$ */
/*
* Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
* Copyright (c) 2010-2012, 2014, 2015 Ingo Schwarze <schwarze@openbsd.org>
* Copyright (c) 2010 Joerg Sonnenberger <joerg@netbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "config.h"
#include <sys/types.h>
#include <sys/param.h> /* MACHINE */
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "mandoc.h"
#include "mandoc_aux.h"
#include "main.h"
#include "mdoc.h"
#include "man.h"
#include "manpath.h"
#include "mansearch.h"
#if !defined(__GNUC__) || (__GNUC__ < 2)
# if !defined(lint)
# define __attribute__(x)
# endif
#endif /* !defined(__GNUC__) || (__GNUC__ < 2) */
enum outmode {
OUTMODE_DEF = 0,
OUTMODE_FLN,
OUTMODE_LST,
OUTMODE_ALL,
OUTMODE_INT,
OUTMODE_ONE
};
typedef void (*out_mdoc)(void *, const struct mdoc *);
typedef void (*out_man)(void *, const struct man *);
typedef void (*out_free)(void *);
enum outt {
OUTT_ASCII = 0, /* -Tascii */
OUTT_LOCALE, /* -Tlocale */
OUTT_UTF8, /* -Tutf8 */
OUTT_TREE, /* -Ttree */
OUTT_MAN, /* -Tman */
OUTT_HTML, /* -Thtml */
OUTT_LINT, /* -Tlint */
OUTT_PS, /* -Tps */
OUTT_PDF /* -Tpdf */
};
struct curparse {
struct mparse *mp;
struct mchars *mchars; /* character table */
enum mandoclevel wlevel; /* ignore messages below this */
int wstop; /* stop after a file with a warning */
enum outt outtype; /* which output to use */
out_mdoc outmdoc; /* mdoc output ptr */
out_man outman; /* man output ptr */
out_free outfree; /* free output ptr */
void *outdata; /* data for output */
char outopts[BUFSIZ]; /* buf of output opts */
};
static int fs_lookup(const struct manpaths *,
size_t ipath, const char *,
const char *, const char *,
struct manpage **, size_t *);
static void fs_search(const struct mansearch *,
const struct manpaths *, int, char**,
struct manpage **, size_t *);
static int koptions(int *, char *);
#if HAVE_SQLITE3
int mandocdb(int, char**);
#endif
static int moptions(int *, char *);
static void mmsg(enum mandocerr, enum mandoclevel,
const char *, int, int, const char *);
static void parse(struct curparse *, int,
const char *, enum mandoclevel *);
static enum mandoclevel passthrough(const char *, int, int);
static void spawn_pager(void);
static int toptions(struct curparse *, char *);
static void usage(enum argmode) __attribute__((noreturn));
static int woptions(struct curparse *, char *);
static const int sec_prios[] = {1, 4, 5, 8, 6, 3, 7, 2, 9};
static char help_arg[] = "help";
static char *help_argv[] = {help_arg, NULL};
static const char *progname;
int
main(int argc, char *argv[])
{
struct curparse curp;
struct mansearch search;
struct manpaths paths;
char *auxpaths;
char *defos;
unsigned char *uc;
struct manpage *res, *resp;
char *conf_file, *defpaths;
size_t isec, i, sz;
int prio, best_prio, synopsis_only;
char sec;
enum mandoclevel rc, rctmp;
enum outmode outmode;
int fd;
int show_usage;
int use_pager;
int options;
int c;
if (argc < 1)
progname = "mandoc";
else if ((progname = strrchr(argv[0], '/')) == NULL)
progname = argv[0];
else
++progname;
#if HAVE_SQLITE3
if (strcmp(progname, BINM_MAKEWHATIS) == 0)
return(mandocdb(argc, argv));
#endif
/* Search options. */
memset(&paths, 0, sizeof(struct manpaths));
conf_file = defpaths = NULL;
auxpaths = NULL;
memset(&search, 0, sizeof(struct mansearch));
search.outkey = "Nd";
if (strcmp(progname, BINM_MAN) == 0)
search.argmode = ARG_NAME;
else if (strcmp(progname, BINM_APROPOS) == 0)
search.argmode = ARG_EXPR;
else if (strcmp(progname, BINM_WHATIS) == 0)
search.argmode = ARG_WORD;
else if (strncmp(progname, "help", 4) == 0)
search.argmode = ARG_NAME;
else
search.argmode = ARG_FILE;
/* Parser and formatter options. */
memset(&curp, 0, sizeof(struct curparse));
curp.outtype = OUTT_LOCALE;
curp.wlevel = MANDOCLEVEL_BADARG;
options = MPARSE_SO | MPARSE_UTF8 | MPARSE_LATIN1;
defos = NULL;
use_pager = 1;
show_usage = 0;
synopsis_only = 0;
outmode = OUTMODE_DEF;
while (-1 != (c = getopt(argc, argv,
"aC:cfhI:iK:klM:m:O:S:s:T:VW:w"))) {
switch (c) {
case 'a':
outmode = OUTMODE_ALL;
break;
case 'C':
conf_file = optarg;
break;
case 'c':
use_pager = 0;
break;
case 'f':
search.argmode = ARG_WORD;
break;
case 'h':
(void)strlcat(curp.outopts, "synopsis,", BUFSIZ);
synopsis_only = 1;
use_pager = 0;
outmode = OUTMODE_ALL;
break;
case 'I':
if (strncmp(optarg, "os=", 3)) {
fprintf(stderr,
"%s: -I %s: Bad argument\n",
progname, optarg);
return((int)MANDOCLEVEL_BADARG);
}
if (defos) {
fprintf(stderr,
"%s: -I %s: Duplicate argument\n",
progname, optarg);
return((int)MANDOCLEVEL_BADARG);
}
defos = mandoc_strdup(optarg + 3);
break;
case 'i':
outmode = OUTMODE_INT;
break;
case 'K':
if ( ! koptions(&options, optarg))
return((int)MANDOCLEVEL_BADARG);
break;
case 'k':
search.argmode = ARG_EXPR;
break;
case 'l':
search.argmode = ARG_FILE;
outmode = OUTMODE_ALL;
break;
case 'M':
defpaths = optarg;
break;
case 'm':
auxpaths = optarg;
break;
case 'O':
search.outkey = optarg;
(void)strlcat(curp.outopts, optarg, BUFSIZ);
(void)strlcat(curp.outopts, ",", BUFSIZ);
break;
case 'S':
search.arch = optarg;
break;
case 's':
search.sec = optarg;
break;
case 'T':
if ( ! toptions(&curp, optarg))
return((int)MANDOCLEVEL_BADARG);
break;
case 'W':
if ( ! woptions(&curp, optarg))
return((int)MANDOCLEVEL_BADARG);
break;
case 'w':
outmode = OUTMODE_FLN;
break;
default:
show_usage = 1;
break;
}
}
if (show_usage)
usage(search.argmode);
/* Postprocess options. */
if (outmode == OUTMODE_DEF) {
switch (search.argmode) {
case ARG_FILE:
outmode = OUTMODE_ALL;
use_pager = 0;
break;
case ARG_NAME:
outmode = OUTMODE_ONE;
break;
default:
outmode = OUTMODE_LST;
break;
}
}
/* Parse arguments. */
if (argc > 0) {
argc -= optind;
argv += optind;
}
resp = NULL;
/*
* Quirks for help(1)
* and for a man(1) section argument without -s.
*/
if (search.argmode == ARG_NAME) {
if (*progname == 'h') {
if (argc == 0) {
argv = help_argv;
argc = 1;
}
} else if (argc > 1 &&
((uc = argv[0]) != NULL) &&
((isdigit(uc[0]) && (uc[1] == '\0' ||
(isalpha(uc[1]) && uc[2] == '\0'))) ||
(uc[0] == 'n' && uc[1] == '\0'))) {
search.sec = uc;
argv++;
argc--;
}
if (search.arch == NULL)
search.arch = getenv("MACHINE");
if (search.arch == NULL)
search.arch = MACHINE;
}
rc = MANDOCLEVEL_OK;
/* man(1), whatis(1), apropos(1) */
if (search.argmode != ARG_FILE) {
if (argc == 0)
usage(search.argmode);
if (search.argmode == ARG_NAME &&
outmode == OUTMODE_ONE)
search.firstmatch = 1;
/* Access the mandoc database. */
manpath_parse(&paths, conf_file, defpaths, auxpaths);
#if HAVE_SQLITE3
mansearch_setup(1);
if( ! mansearch(&search, &paths, argc, argv, &res, &sz))
usage(search.argmode);
#else
if (search.argmode != ARG_NAME) {
fputs("mandoc: database support not compiled in\n",
stderr);
return((int)MANDOCLEVEL_BADARG);
}
sz = 0;
#endif
if (sz == 0 && search.argmode == ARG_NAME)
fs_search(&search, &paths, argc, argv, &res, &sz);
if (sz == 0) {
rc = MANDOCLEVEL_BADARG;
goto out;
}
/*
* For standard man(1) and -a output mode,
* prepare for copying filename pointers
* into the program parameter array.
*/
if (outmode == OUTMODE_ONE) {
argc = 1;
best_prio = 10;
} else if (outmode == OUTMODE_ALL)
argc = (int)sz;
/* Iterate all matching manuals. */
resp = res;
for (i = 0; i < sz; i++) {
if (outmode == OUTMODE_FLN)
puts(res[i].file);
else if (outmode == OUTMODE_LST)
printf("%s - %s\n", res[i].names,
res[i].output == NULL ? "" :
res[i].output);
else if (outmode == OUTMODE_ONE) {
/* Search for the best section. */
isec = strcspn(res[i].file, "123456789");
sec = res[i].file[isec];
if ('\0' == sec)
continue;
prio = sec_prios[sec - '1'];
if (prio >= best_prio)
continue;
best_prio = prio;
resp = res + i;
}
}
/*
* For man(1), -a and -i output mode, fall through
* to the main mandoc(1) code iterating files
* and running the parsers on each of them.
*/
if (outmode == OUTMODE_FLN || outmode == OUTMODE_LST)
goto out;
}
/* mandoc(1) */
if (search.argmode == ARG_FILE && ! moptions(&options, auxpaths))
return((int)MANDOCLEVEL_BADARG);
curp.mchars = mchars_alloc();
curp.mp = mparse_alloc(options, curp.wlevel, mmsg,
curp.mchars, defos);
/*
* Conditionally start up the lookaside buffer before parsing.
*/
if (OUTT_MAN == curp.outtype)
mparse_keep(curp.mp);
if (argc < 1) {
if (use_pager && isatty(STDOUT_FILENO))
spawn_pager();
parse(&curp, STDIN_FILENO, "<stdin>", &rc);
}
while (argc > 0) {
rctmp = mparse_open(curp.mp, &fd,
resp != NULL ? resp->file : *argv);
if (rc < rctmp)
rc = rctmp;
if (fd != -1) {
if (use_pager && isatty(STDOUT_FILENO))
spawn_pager();
use_pager = 0;
if (resp == NULL)
parse(&curp, fd, *argv, &rc);
else if (resp->form & FORM_SRC) {
/* For .so only; ignore failure. */
chdir(paths.paths[resp->ipath]);
parse(&curp, fd, resp->file, &rc);
} else {
rctmp = passthrough(resp->file, fd,
synopsis_only);
if (rc < rctmp)
rc = rctmp;
}
rctmp = mparse_wait(curp.mp);
if (rc < rctmp)
rc = rctmp;
if (argc > 1 && curp.outtype <= OUTT_UTF8)
ascii_sepline(curp.outdata);
}
if (MANDOCLEVEL_OK != rc && curp.wstop)
break;
if (resp != NULL)
resp++;
else
argv++;
if (--argc)
mparse_reset(curp.mp);
}
if (curp.outfree)
(*curp.outfree)(curp.outdata);
mparse_free(curp.mp);
mchars_free(curp.mchars);
out:
if (search.argmode != ARG_FILE) {
manpath_free(&paths);
#if HAVE_SQLITE3
mansearch_free(res, sz);
mansearch_setup(0);
#endif
}
free(defos);
return((int)rc);
}
static void
usage(enum argmode argmode)
{
switch (argmode) {
case ARG_FILE:
fputs("usage: mandoc [-acfhkl] [-Ios=name] "
"[-Kencoding] [-mformat] [-Ooption]\n"
"\t [-Toutput] [-Wlevel] [file ...]\n", stderr);
break;
case ARG_NAME:
fputs("usage: man [-acfhklw] [-C file] [-I os=name] "
"[-K encoding] [-M path] [-m path]\n"
"\t [-O option=value] [-S subsection] [-s section] "
"[-T output] [-W level]\n"
"\t [section] name ...\n", stderr);
break;
case ARG_WORD:
fputs("usage: whatis [-acfhklw] [-C file] "
"[-M path] [-m path] [-O outkey] [-S arch]\n"
"\t [-s section] name ...\n", stderr);
break;
case ARG_EXPR:
fputs("usage: apropos [-acfhklw] [-C file] "
"[-M path] [-m path] [-O outkey] [-S arch]\n"
"\t [-s section] expression ...\n", stderr);
break;
}
exit((int)MANDOCLEVEL_BADARG);
}
static int
fs_lookup(const struct manpaths *paths, size_t ipath,
const char *sec, const char *arch, const char *name,
struct manpage **res, size_t *ressz)
{
struct manpage *page;
char *file;
int form;
mandoc_asprintf(&file, "%s/man%s/%s.%s",
paths->paths[ipath], sec, name, sec);
if (access(file, R_OK) != -1) {
form = FORM_SRC;
goto found;
}
free(file);
mandoc_asprintf(&file, "%s/cat%s/%s.0",
paths->paths[ipath], sec, name);
if (access(file, R_OK) != -1) {
form = FORM_CAT;
goto found;
}
free(file);
if (arch != NULL) {
mandoc_asprintf(&file, "%s/man%s/%s/%s.%s",
paths->paths[ipath], sec, arch, name, sec);
if (access(file, R_OK) != -1) {
form = FORM_SRC;
goto found;
}
free(file);
}
return(0);
found:
#if HAVE_SQLITE3
fprintf(stderr, "%s: outdated mandoc.db lacks %s(%s) entry,\n"
" consider running # makewhatis %s\n",
progname, name, sec, paths->paths[ipath]);
#endif
*res = mandoc_reallocarray(*res, ++*ressz, sizeof(struct manpage));
page = *res + (*ressz - 1);
page->file = file;
page->names = NULL;
page->output = NULL;
page->ipath = ipath;
page->bits = NAME_FILE & NAME_MASK;
page->sec = (*sec >= '1' && *sec <= '9') ? *sec - '1' + 1 : 10;
page->form = form;
return(1);
}
static void
fs_search(const struct mansearch *cfg, const struct manpaths *paths,
int argc, char **argv, struct manpage **res, size_t *ressz)
{
const char *const sections[] =
{"1", "8", "6", "2", "3", "3p", "5", "7", "4", "9"};
const size_t nsec = sizeof(sections)/sizeof(sections[0]);
size_t ipath, isec, lastsz;
assert(cfg->argmode == ARG_NAME);
*res = NULL;
*ressz = lastsz = 0;
while (argc) {
for (ipath = 0; ipath < paths->sz; ipath++) {
if (cfg->sec != NULL) {
if (fs_lookup(paths, ipath, cfg->sec,
cfg->arch, *argv, res, ressz) &&
cfg->firstmatch)
return;
} else for (isec = 0; isec < nsec; isec++)
if (fs_lookup(paths, ipath, sections[isec],
cfg->arch, *argv, res, ressz) &&
cfg->firstmatch)
return;
}
if (*ressz == lastsz)
fprintf(stderr,
"%s: No entry for %s in the manual.\n",
progname, *argv);
lastsz = *ressz;
argv++;
argc--;
}
}
static void
parse(struct curparse *curp, int fd, const char *file,
enum mandoclevel *level)
{
enum mandoclevel rc;
struct mdoc *mdoc;
struct man *man;
/* Begin by parsing the file itself. */
assert(file);
assert(fd >= -1);
rc = mparse_readfd(curp->mp, fd, file);
/*
* With -Wstop and warnings or errors of at least the requested
* level, do not produce output.
*/
if (MANDOCLEVEL_OK != rc && curp->wstop)
goto cleanup;
/* If unset, allocate output dev now (if applicable). */
if ( ! (curp->outman && curp->outmdoc)) {
switch (curp->outtype) {
case OUTT_HTML:
curp->outdata = html_alloc(curp->mchars,
curp->outopts);
curp->outfree = html_free;
break;
case OUTT_UTF8:
curp->outdata = utf8_alloc(curp->mchars,
curp->outopts);
curp->outfree = ascii_free;
break;
case OUTT_LOCALE:
curp->outdata = locale_alloc(curp->mchars,
curp->outopts);
curp->outfree = ascii_free;
break;
case OUTT_ASCII:
curp->outdata = ascii_alloc(curp->mchars,
curp->outopts);
curp->outfree = ascii_free;
break;
case OUTT_PDF:
curp->outdata = pdf_alloc(curp->mchars,
curp->outopts);
curp->outfree = pspdf_free;
break;
case OUTT_PS:
curp->outdata = ps_alloc(curp->mchars,
curp->outopts);
curp->outfree = pspdf_free;
break;
default:
break;
}
switch (curp->outtype) {
case OUTT_HTML:
curp->outman = html_man;
curp->outmdoc = html_mdoc;
break;
case OUTT_TREE:
curp->outman = tree_man;
curp->outmdoc = tree_mdoc;
break;
case OUTT_MAN:
curp->outmdoc = man_mdoc;
curp->outman = man_man;
break;
case OUTT_PDF:
/* FALLTHROUGH */
case OUTT_ASCII:
/* FALLTHROUGH */
case OUTT_UTF8:
/* FALLTHROUGH */
case OUTT_LOCALE:
/* FALLTHROUGH */
case OUTT_PS:
curp->outman = terminal_man;
curp->outmdoc = terminal_mdoc;
break;
default:
break;
}
}
mparse_result(curp->mp, &mdoc, &man, NULL);
/* Execute the out device, if it exists. */
if (man && curp->outman)
(*curp->outman)(curp->outdata, man);
if (mdoc && curp->outmdoc)
(*curp->outmdoc)(curp->outdata, mdoc);
cleanup:
if (*level < rc)
*level = rc;
}
static enum mandoclevel
passthrough(const char *file, int fd, int synopsis_only)
{
const char synb[] = "S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS";
const char synr[] = "SYNOPSIS";
FILE *stream;
const char *syscall;
char *line;
size_t len, off;
ssize_t nw;
int print;
fflush(stdout);
if ((stream = fdopen(fd, "r")) == NULL) {
close(fd);
syscall = "fdopen";
goto fail;
}
print = 0;
while ((line = fgetln(stream, &len)) != NULL) {
if (synopsis_only) {
if (print) {
if ( ! isspace((unsigned char)*line))
goto done;
while (len &&
isspace((unsigned char)*line)) {
line++;
len--;
}
} else {
if ((len == sizeof(synb) &&
! strncmp(line, synb, len - 1)) ||
(len == sizeof(synr) &&
! strncmp(line, synr, len - 1)))
print = 1;
continue;
}
}
for (off = 0; off < len; off += nw)
if ((nw = write(STDOUT_FILENO, line + off,
len - off)) == -1 || nw == 0) {
fclose(stream);
syscall = "write";
goto fail;
}
}
if (ferror(stream)) {
fclose(stream);
syscall = "fgetln";
goto fail;
}
done:
fclose(stream);
return(MANDOCLEVEL_OK);
fail:
fprintf(stderr, "%s: %s: SYSERR: %s: %s",
progname, file, syscall, strerror(errno));
return(MANDOCLEVEL_SYSERR);
}
static int
koptions(int *options, char *arg)
{
if ( ! strcmp(arg, "utf-8")) {
*options |= MPARSE_UTF8;
*options &= ~MPARSE_LATIN1;
} else if ( ! strcmp(arg, "iso-8859-1")) {
*options |= MPARSE_LATIN1;
*options &= ~MPARSE_UTF8;
} else if ( ! strcmp(arg, "us-ascii")) {
*options &= ~(MPARSE_UTF8 | MPARSE_LATIN1);
} else {
fprintf(stderr, "%s: -K %s: Bad argument\n",
progname, arg);
return(0);
}
return(1);
}
static int
moptions(int *options, char *arg)
{
if (arg == NULL)
/* nothing to do */;
else if (0 == strcmp(arg, "doc"))
*options |= MPARSE_MDOC;
else if (0 == strcmp(arg, "andoc"))
/* nothing to do */;
else if (0 == strcmp(arg, "an"))
*options |= MPARSE_MAN;
else {
fprintf(stderr, "%s: -m %s: Bad argument\n",
progname, arg);
return(0);
}
return(1);
}
static int
toptions(struct curparse *curp, char *arg)
{
if (0 == strcmp(arg, "ascii"))
curp->outtype = OUTT_ASCII;
else if (0 == strcmp(arg, "lint")) {
curp->outtype = OUTT_LINT;
curp->wlevel = MANDOCLEVEL_WARNING;
} else if (0 == strcmp(arg, "tree"))
curp->outtype = OUTT_TREE;
else if (0 == strcmp(arg, "man"))
curp->outtype = OUTT_MAN;
else if (0 == strcmp(arg, "html"))
curp->outtype = OUTT_HTML;
else if (0 == strcmp(arg, "utf8"))
curp->outtype = OUTT_UTF8;
else if (0 == strcmp(arg, "locale"))
curp->outtype = OUTT_LOCALE;
else if (0 == strcmp(arg, "xhtml"))
curp->outtype = OUTT_HTML;
else if (0 == strcmp(arg, "ps"))
curp->outtype = OUTT_PS;
else if (0 == strcmp(arg, "pdf"))
curp->outtype = OUTT_PDF;
else {
fprintf(stderr, "%s: -T %s: Bad argument\n",
progname, arg);
return(0);
}
return(1);
}
static int
woptions(struct curparse *curp, char *arg)
{
char *v, *o;
const char *toks[7];
toks[0] = "stop";
toks[1] = "all";
toks[2] = "warning";
toks[3] = "error";
toks[4] = "unsupp";
toks[5] = "fatal";
toks[6] = NULL;
while (*arg) {
o = arg;
switch (getsubopt(&arg, UNCONST(toks), &v)) {
case 0:
curp->wstop = 1;
break;
case 1:
/* FALLTHROUGH */
case 2:
curp->wlevel = MANDOCLEVEL_WARNING;
break;
case 3:
curp->wlevel = MANDOCLEVEL_ERROR;
break;
case 4:
curp->wlevel = MANDOCLEVEL_UNSUPP;
break;
case 5:
curp->wlevel = MANDOCLEVEL_BADARG;
break;
default:
fprintf(stderr, "%s: -W %s: Bad argument\n",
progname, o);
return(0);
}
}
return(1);
}
static void
mmsg(enum mandocerr t, enum mandoclevel lvl,
const char *file, int line, int col, const char *msg)
{
const char *mparse_msg;
fprintf(stderr, "%s: %s:", progname, file);
if (line)
fprintf(stderr, "%d:%d:", line, col + 1);
fprintf(stderr, " %s", mparse_strlevel(lvl));
if (NULL != (mparse_msg = mparse_strerror(t)))
fprintf(stderr, ": %s", mparse_msg);
if (msg)
fprintf(stderr, ": %s", msg);
fputc('\n', stderr);
}
static void
spawn_pager(void)
{
#define MAX_PAGER_ARGS 16
char *argv[MAX_PAGER_ARGS];
const char *pager;
char *cp;
int fildes[2];
int argc;
if (pipe(fildes) == -1) {
fprintf(stderr, "%s: pipe: %s\n",
progname, strerror(errno));
return;
}
switch (fork()) {
case -1:
fprintf(stderr, "%s: fork: %s\n",
progname, strerror(errno));
exit((int)MANDOCLEVEL_SYSERR);
case 0:
close(fildes[0]);
if (dup2(fildes[1], STDOUT_FILENO) == -1) {
fprintf(stderr, "%s: dup output: %s\n",
progname, strerror(errno));
exit((int)MANDOCLEVEL_SYSERR);
}
return;
default:
break;
}
/* The original process becomes the pager. */
close(fildes[1]);
if (dup2(fildes[0], STDIN_FILENO) == -1) {
fprintf(stderr, "%s: dup input: %s\n",
progname, strerror(errno));
exit((int)MANDOCLEVEL_SYSERR);
}
pager = getenv("MANPAGER");
if (pager == NULL || *pager == '\0')
pager = getenv("PAGER");
if (pager == NULL || *pager == '\0')
pager = "/usr/bin/more -s";
cp = mandoc_strdup(pager);
/*
* Parse the pager command into words.
* Intentionally do not do anything fancy here.
*/
argc = 0;
while (argc + 1 < MAX_PAGER_ARGS) {
argv[argc++] = cp;
cp = strchr(cp, ' ');
if (cp == NULL)
break;
*cp++ = '\0';
while (*cp == ' ')
cp++;
if (*cp == '\0')
break;
}
argv[argc] = NULL;
/* Hand over to the pager. */
execvp(argv[0], argv);
fprintf(stderr, "%s: exec: %s\n",
progname, strerror(errno));
exit((int)MANDOCLEVEL_SYSERR);
}