cosmopolitan/libc/x/paginate.c
Gavin Hayes 2bfd6b37c1
Various paginate improvements (#1148)
* start on improving __paginate

* make __paginate more robust

* add __paginate_file

* cleanup __paginate unlinking
2024-04-26 23:12:25 -04:00

109 lines
4.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et 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/calls/syscall_support-nt.internal.h"
#include "libc/dce.h"
#include "libc/intrin/safemacros.internal.h"
#include "libc/limits.h"
#include "libc/mem/gc.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/o.h"
#include "libc/temp.h"
#include "libc/x/x.h"
static char *get_pagerpath(char *pathbuf, size_t pathbufsz) {
char *pagerpath;
if (strcmp(nulltoempty(getenv("TERM")), "dumb") && isatty(0) && isatty(1) &&
((pagerpath = commandv("less", pathbuf, pathbufsz)) ||
(pagerpath = commandv("more", pathbuf, pathbufsz)) ||
(pagerpath = commandv("more.exe", pathbuf, pathbufsz)) ||
(pagerpath = commandv("more.com", pathbuf, pathbufsz)))) {
return pagerpath;
}
return 0;
}
static bool run_pager(char *args[hasatleast 3]) {
char16_t widepath[PATH_MAX];
int n, pid;
if (IsWindows() && !strcasecmp(args[0], "/C/Windows/System32/more.com") &&
(((n = __mkntpath(args[1], widepath)) == -1) ||
!(args[1] = gc(utf16to8(widepath, n, 0))))) {
return false;
}
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);
return true;
}
return false;
}
/**
* Displays wall of text in terminal with pagination.
*/
void __paginate(int fd, const char *s) {
int tfd;
char *args[3] = {0};
char tmppath[] = "/tmp/paginate.XXXXXX";
char progpath[PATH_MAX];
bool done;
if ((args[0] = get_pagerpath(progpath, sizeof(progpath)))) {
if ((tfd = mkstemp(tmppath)) != -1) {
write(tfd, s, strlen(s));
close(tfd);
args[1] = tmppath;
done = run_pager(args);
unlink(tmppath);
if (done) {
return;
}
}
}
write(fd, s, strlen(s));
}
/**
* Displays a file in terminal with pagination
*/
void __paginate_file(int fd, const char *path) {
char *args[3] = {0};
char progpath[PATH_MAX];
if ((args[0] = get_pagerpath(progpath, sizeof(progpath)))) {
args[1] = (char *)path;
if (run_pager(args)) {
return;
}
}
int sfd = open(path, O_RDONLY);
if (sfd != -1) {
ssize_t n;
while ((n = read(sfd, progpath, sizeof(progpath)) > 0)) {
write(fd, progpath, n);
}
}
close(sfd);
}