2 * Copyright (C) 2016 Jo-Philipp Wich <jo@mein.io>
3 * Copyright (C) 2016 Felix Fietkau <nbd@nbd.name>
5 * Zlib decrompression utility routines.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU Library General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
33 static void to_devnull(int fd)
35 int devnull = open("/dev/null", fd ? O_WRONLY : O_RDONLY);
40 if (devnull > STDERR_FILENO)
44 void *gzip_thread(void *ptr)
46 struct gzip_handle *zh = ptr;
52 len = fread(buf, 1, sizeof(buf), zh->file);
54 len = gzip_read(zh->gzip, buf, sizeof(buf));
60 ret = write(zh->wfd, buf, len);
61 } while (ret == -1 && errno == EINTR);
68 int gzip_exec(struct gzip_handle *zh, const char *filename)
70 int rpipe[2] = { -1, -1 }, wpipe[2] = {
72 struct sigaction pipe_sa = {.sa_handler = SIG_IGN };
77 if (sigaction(SIGPIPE, &pipe_sa, &zh->pipe_sa) < 0)
83 if (!filename && pipe(wpipe) < 0) {
96 to_devnull(STDERR_FILENO);
99 to_devnull(STDIN_FILENO);
101 dup2(wpipe[0], STDIN_FILENO);
106 dup2(rpipe[1], STDOUT_FILENO);
110 execlp("gzip", "gzip", "-d", "-c", filename, NULL);
117 fcntl(zh->rfd, F_SETFD, fcntl(zh->rfd, F_GETFD) | FD_CLOEXEC);
121 fcntl(zh->wfd, F_SETFD,
122 fcntl(zh->wfd, F_GETFD) | FD_CLOEXEC);
124 pthread_create(&zh->thread, NULL, gzip_thread, zh);
131 ssize_t gzip_read(struct gzip_handle * zh, char *buf, ssize_t len)
136 ret = read(zh->rfd, buf, len);
137 } while (ret == -1 && errno != EINTR);
142 ssize_t gzip_copy(struct gzip_handle * zh, FILE * out, ssize_t len)
145 ssize_t rlen, total = 0;
148 rlen = gzip_read(zh, buf,
149 (len > sizeof(buf)) ? sizeof(buf) : len);
155 if (fwrite(buf, 1, rlen, out) != rlen)
166 FILE *gzip_fdopen(struct gzip_handle * zh, const char *filename)
168 memset(zh, 0, sizeof(*zh));
170 if (!filename || gzip_exec(zh, filename) < 0)
173 fcntl(zh->rfd, F_SETFL, fcntl(zh->rfd, F_GETFL) & ~O_NONBLOCK);
175 return fdopen(zh->rfd, "r");
178 int gzip_close(struct gzip_handle *zh)
189 kill(zh->pid, SIGKILL);
190 waitpid(zh->pid, &code, 0);
197 pthread_join(zh->thread, NULL);
199 sigaction(SIGPIPE, &zh->pipe_sa, NULL);
201 return WIFEXITED(code) ? WEXITSTATUS(code) : -1;