cosmopolitan/libc/stdio/paginate.c
2022-12-11 14:30:59 -08:00

62 lines
3.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2022 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or 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 "libc/calls/calls.h"
#include "libc/fmt/fmt.h"
#include "libc/intrin/safemacros.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/stdio/stdio.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/o.h"
#include "libc/x/x.h"
/**
* Displays wall of text in terminal with pagination.
*/
void __paginate(int fd, const char *s) {
int tfd, pid;
char *args[3] = {0};
char tmppath[PATH_MAX];
char progpath[PATH_MAX];
if (strcmp(nulltoempty(getenv("TERM")), "dumb") && isatty(0) && isatty(1) &&
((args[0] = commandv("less", progpath, sizeof(progpath))) ||
(args[0] = commandv("more", progpath, sizeof(progpath))))) {
snprintf(tmppath, sizeof(tmppath), "%s%s-%s-%d.txt", kTmpPath,
firstnonnull(program_invocation_short_name, "unknown"), "paginate",
getpid());
if ((tfd = open(tmppath, O_WRONLY | O_CREAT | O_TRUNC, 0644)) != -1) {
write(tfd, s, strlen(s));
close(tfd);
args[1] = tmppath;
if ((pid = fork()) != -1) {
putenv("LC_ALL=C.UTF-8");
putenv("LESSCHARSET=utf-8");
putenv("LESS=-RS");
if (!pid) {
execv(args[0], args);
_Exit(127);
}
waitpid(pid, 0, 0);
unlink(tmppath);
return;
}
unlink(tmppath);
}
}
write(fd, s, strlen(s));
}