diff options
-rw-r--r-- | bin/.gitignore | 1 | ||||
-rw-r--r-- | bin/Makefile | 2 | ||||
-rw-r--r-- | bin/pngs.c | 75 |
3 files changed, 77 insertions, 1 deletions
diff --git a/bin/.gitignore b/bin/.gitignore index ae5a47b8..cb1d47f3 100644 --- a/bin/.gitignore +++ b/bin/.gitignore @@ -7,6 +7,7 @@ hnel pbcopy pbd pbpaste +pngs wake xx jrp diff --git a/bin/Makefile b/bin/Makefile index 708860c6..44454bff 100644 --- a/bin/Makefile +++ b/bin/Makefile @@ -1,4 +1,4 @@ -ANY_BINS = atch dtch gfxx hnel pbcopy pbd pbpaste wake xx +ANY_BINS = atch dtch gfxx hnel pbcopy pbd pbpaste pngs wake xx BSD_BINS = jrp klon typo watch LIN_BINS = bri fbatt fbclock ALL_BINS = $(ANY_BINS) $(BSD_BINS) $(LIN_BINS) diff --git a/bin/pngs.c b/bin/pngs.c new file mode 100644 index 00000000..b0768d64 --- /dev/null +++ b/bin/pngs.c @@ -0,0 +1,75 @@ +/* Copyright (c) 2018, Curtis McEnroe <programble@gmail.com> + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero 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 Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <err.h> +#include <fcntl.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sysexits.h> +#include <unistd.h> + +static const uint8_t SIGNATURE[] = { 0x89, 'P', 'N', 'G', '\r', '\n', 0x1A, '\n' }; +static const uint8_t IEND[] = { 'I', 'E', 'N', 'D' }; + +static unsigned counter; +static char path[FILENAME_MAX]; +static int fd; + +static void next(const char *prefix) { + if (counter++) { + int error = close(fd); + if (error) err(EX_IOERR, "%s", path); + } + snprintf(path, sizeof(path), "%s%04u.png", prefix, counter); + fd = open(path, O_WRONLY | O_CREAT | O_EXCL, 0644); + if (fd < 0) err(EX_CANTCREAT, "%s", path); + printf("%s\n", path); +} + +static void writeAll(const uint8_t *buf, size_t size) { + while (size) { + ssize_t writeSize = write(fd, buf, size); + if (writeSize < 0) err(EX_IOERR, "%s", path); + buf += writeSize; + size -= writeSize; + } +} + +int main(int argc, char *argv[]) { + const char *prefix = (argc > 1) ? argv[1] : ""; + + for (;;) { + uint8_t buf[4096]; + ssize_t size = read(STDIN_FILENO, buf, sizeof(buf)); + if (size < 0) err(EX_IOERR, "read"); + if (!size) return EX_OK; + + const uint8_t *signature = memmem(buf, size, SIGNATURE, sizeof(SIGNATURE)); + if (signature) { + writeAll(buf, signature - buf); + next(prefix); + writeAll(signature, size - (signature - buf)); + } else { + const uint8_t *iend = memmem(buf, size, IEND, sizeof(IEND)); + if (iend && iend - buf < size - 8) { + warnx("trailing data, a PNG may be skipped"); + } + writeAll(buf, size); + } + } +} |