diff options
Diffstat (limited to 'bin/pngo.c')
| -rw-r--r-- | bin/pngo.c | 812 |
1 files changed, 812 insertions, 0 deletions
diff --git a/bin/pngo.c b/bin/pngo.c new file mode 100644 index 00000000..322cb1ba --- /dev/null +++ b/bin/pngo.c @@ -0,0 +1,812 @@ +/* Copyright (C) 2018 C. McEnroe <june@causal.agency> + * + * 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 <arpa/inet.h> +#include <err.h> +#include <stdbool.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sysexits.h> +#include <unistd.h> +#include <zlib.h> + +#define PACKED __attribute__((packed)) +#define PAIR(a, b) ((uint16_t)(a) << 8 | (uint16_t)(b)) + +#define CRC_INIT (crc32(0, Z_NULL, 0)) + +static bool verbose; +static const char *path; +static FILE *file; +static uint32_t crc; + +static void readExpect(void *ptr, size_t size, const char *expect) { + fread(ptr, size, 1, file); + if (ferror(file)) err(EX_IOERR, "%s", path); + if (feof(file)) errx(EX_DATAERR, "%s: missing %s", path, expect); + crc = crc32(crc, ptr, size); +} + +static void writeExpect(const void *ptr, size_t size) { + fwrite(ptr, size, 1, file); + if (ferror(file)) err(EX_IOERR, "%s", path); + crc = crc32(crc, ptr, size); +} + +static const uint8_t Signature[8] = "\x89PNG\r\n\x1A\n"; + +static void readSignature(void) { + uint8_t signature[8]; + readExpect(signature, 8, "signature"); + if (0 != memcmp(signature, Signature, 8)) { + errx(EX_DATAERR, "%s: invalid signature", path); + } +} + +static void writeSignature(void) { + writeExpect(Signature, sizeof(Signature)); +} + +struct PACKED Chunk { + uint32_t size; + char type[4]; +}; + +static const char *typeStr(struct Chunk chunk) { + static char buf[5]; + memcpy(buf, chunk.type, 4); + return buf; +} + +static struct Chunk readChunk(void) { + struct Chunk chunk; + readExpect(&chunk, sizeof(chunk), "chunk"); + chunk.size = ntohl(chunk.size); + crc = crc32(CRC_INIT, (Byte *)chunk.type, sizeof(chunk.type)); + return chunk; +} + +static void writeChunk(struct Chunk chunk) { + chunk.size = htonl(chunk.size); + writeExpect(&chunk, sizeof(chunk)); + crc = crc32(CRC_INIT, (Byte *)chunk.type, sizeof(chunk.type)); +} + +static void readCrc(void) { + uint32_t expected = crc; + uint32_t found; + readExpect(&found, sizeof(found), "CRC32"); + found = ntohl(found); + if (found != expected) { + errx( + EX_DATAERR, "%s: expected CRC32 %08X, found %08X", + path, expected, found + ); + } +} + +static void writeCrc(void) { + uint32_t net = htonl(crc); + writeExpect(&net, sizeof(net)); +} + +static void skipChunk(struct Chunk chunk) { + if (!(chunk.type[0] & 0x20)) { + errx(EX_CONFIG, "%s: unsupported critical chunk %s", path, typeStr(chunk)); + } + uint8_t discard[4096]; + while (chunk.size > sizeof(discard)) { + readExpect(discard, sizeof(discard), "chunk data"); + chunk.size -= sizeof(discard); + } + if (chunk.size) readExpect(discard, chunk.size, "chunk data"); + readCrc(); +} + +static struct PACKED { + uint32_t width; + uint32_t height; + uint8_t depth; + enum PACKED { + Grayscale = 0, + Truecolor = 2, + Indexed = 3, + GrayscaleAlpha = 4, + TruecolorAlpha = 6, + } color; + enum PACKED { Deflate } compression; + enum PACKED { Adaptive } filter; + enum PACKED { Progressive, Adam7 } interlace; +} header; +_Static_assert(13 == sizeof(header), "header size"); + +static size_t pixelBits(void) { + switch (header.color) { + case Grayscale: return 1 * header.depth; + case Truecolor: return 3 * header.depth; + case Indexed: return 1 * header.depth; + case GrayscaleAlpha: return 2 * header.depth; + case TruecolorAlpha: return 4 * header.depth; + default: abort(); + } +} + +static size_t pixelSize(void) { + return (pixelBits() + 7) / 8; +} + +static size_t lineSize(void) { + return (header.width * pixelBits() + 7) / 8; +} + +static size_t dataSize(void) { + return (1 + lineSize()) * header.height; +} + +static const char *ColorStr[] = { + [Grayscale] = "grayscale", + [Truecolor] = "truecolor", + [Indexed] = "indexed", + [GrayscaleAlpha] = "grayscale alpha", + [TruecolorAlpha] = "truecolor alpha", +}; +static void printHeader(void) { + fprintf( + stderr, + "%s: %ux%u %hhu-bit %s\n", + path, + header.width, header.height, + header.depth, ColorStr[header.color] + ); +} + +static void readHeader(struct Chunk chunk) { + if (chunk.size != sizeof(header)) { + errx( + EX_DATAERR, "%s: expected IHDR size %zu, found %u", + path, sizeof(header), chunk.size + ); + } + readExpect(&header, sizeof(header), "header"); + readCrc(); + + header.width = ntohl(header.width); + header.height = ntohl(header.height); + + if (!header.width) errx(EX_DATAERR, "%s: invalid width 0", path); + if (!header.height) errx(EX_DATAERR, "%s: invalid height 0", path); + switch (PAIR(header.color, header.depth)) { + case PAIR(Grayscale, 1): + case PAIR(Grayscale, 2): + case PAIR(Grayscale, 4): + case PAIR(Grayscale, 8): + case PAIR(Grayscale, 16): + case PAIR(Truecolor, 8): + case PAIR(Truecolor, 16): + case PAIR(Indexed, 1): + case PAIR(Indexed, 2): + case PAIR(Indexed, 4): + case PAIR(Indexed, 8): + case PAIR(GrayscaleAlpha, 8): + case PAIR(GrayscaleAlpha, 16): + case PAIR(TruecolorAlpha, 8): + case PAIR(TruecolorAlpha, 16): + break; + default: + errx( + EX_DATAERR, "%s: invalid color type %hhu and bit depth %hhu", + path, header.color, header.depth + ); + } + if (header.compression != Deflate) { + errx( + EX_DATAERR, "%s: invalid compression method %hhu", + path, header.compression + ); + } + if (header.filter != Adaptive) { + errx(EX_DATAERR, "%s: invalid filter method %hhu", path, header.filter); + } + if (header.interlace > Adam7) { + errx(EX_DATAERR, "%s: invalid interlace method %hhu", path, header.interlace); + } + + if (verbose) printHeader(); +} + +static void writeHeader(void) { + if (verbose) printHeader(); + + struct Chunk ihdr = { .size = sizeof(header), .type = "IHDR" }; + writeChunk(ihdr); + header.width = htonl(header.width); + header.height = htonl(header.height); + writeExpect(&header, sizeof(header)); + writeCrc(); + + header.width = ntohl(header.width); + header.height = ntohl(header.height); +} + +static struct { + uint32_t len; + uint8_t entries[256][3]; +} palette; + +static struct { + uint32_t len; + uint8_t alpha[256]; +} trans; + +static void paletteClear(void) { + palette.len = 0; + trans.len = 0; +} + +static uint32_t paletteIndex(bool alpha, const uint8_t *rgba) { + uint32_t i; + for (i = 0; i < palette.len; ++i) { + if (alpha && i < trans.len && trans.alpha[i] != rgba[3]) continue; + if (0 == memcmp(palette.entries[i], rgba, 3)) break; + } + return i; +} + +static bool paletteAdd(bool alpha, const uint8_t *rgba) { + uint32_t i = paletteIndex(alpha, rgba); + if (i < palette.len) return true; + if (i == 256) return false; + memcpy(palette.entries[i], rgba, 3); + palette.len++; + if (alpha) { + trans.alpha[i] = rgba[3]; + trans.len++; + } + return true; +} + +static void transCompact(void) { + uint32_t i; + for (i = 0; i < trans.len; ++i) { + if (trans.alpha[i] == 0xFF) break; + } + if (i == trans.len) return; + + for (uint32_t j = i + 1; j < trans.len; ++j) { + if (trans.alpha[j] == 0xFF) continue; + + uint8_t alpha = trans.alpha[i]; + trans.alpha[i] = trans.alpha[j]; + trans.alpha[j] = alpha; + + uint8_t rgb[3]; + memcpy(rgb, palette.entries[i], 3); + memcpy(palette.entries[i], palette.entries[j], 3); + memcpy(palette.entries[j], rgb, 3); + + i++; + } + trans.len = i; +} + +static void readPalette(struct Chunk chunk) { + if (chunk.size % 3) { + errx(EX_DATAERR, "%s: PLTE size %u not divisible by 3", path, chunk.size); + } + + palette.len = chunk.size / 3; + if (palette.len > 256) { + errx(EX_DATAERR, "%s: PLTE length %u > 256", path, palette.len); + } + + readExpect(palette.entries, chunk.size, "palette data"); + readCrc(); + + if (verbose) fprintf(stderr, "%s: palette length %u\n", path, palette.len); +} + +static void writePalette(void) { + if (verbose) fprintf(stderr, "%s: palette length %u\n", path, palette.len); + struct Chunk plte = { .size = 3 * palette.len, .type = "PLTE" }; + writeChunk(plte); + writeExpect(palette.entries, plte.size); + writeCrc(); +} + +static void readTrans(struct Chunk chunk) { + trans.len = chunk.size; + if (trans.len > 256) { + errx(EX_DATAERR, "%s: tRNS length %u > 256", path, trans.len); + } + readExpect(trans.alpha, chunk.size, "transparency alpha"); + readCrc(); + if (verbose) fprintf(stderr, "%s: transparency length %u\n", path, trans.len); +} + +static void writeTrans(void) { + if (verbose) fprintf(stderr, "%s: transparency length %u\n", path, trans.len); + struct Chunk trns = { .size = trans.len, .type = "tRNS" }; + writeChunk(trns); + writeExpect(trans.alpha, trns.size); + writeCrc(); +} + +static uint8_t *data; + +static void allocData(void) { + data = malloc(dataSize()); + if (!data) err(EX_OSERR, "malloc(%zu)", dataSize()); +} + +static void readData(struct Chunk chunk) { + if (verbose) fprintf(stderr, "%s: data size %zu\n", path, dataSize()); + + struct z_stream_s stream = { .next_out = data, .avail_out = dataSize() }; + int error = inflateInit(&stream); + if (error != Z_OK) errx(EX_SOFTWARE, "%s: inflateInit: %s", path, stream.msg); + + for (;;) { + if (0 != memcmp(chunk.type, "IDAT", 4)) { + errx(EX_DATAERR, "%s: missing IDAT chunk", path); + } + + uint8_t *idat = malloc(chunk.size); + if (!idat) err(EX_OSERR, "malloc"); + + readExpect(idat, chunk.size, "image data"); + readCrc(); + + stream.next_in = idat; + stream.avail_in = chunk.size; + int error = inflate(&stream, Z_SYNC_FLUSH); + free(idat); + + if (error == Z_STREAM_END) break; + if (error != Z_OK) { + errx(EX_DATAERR, "%s: inflate: %s", path, stream.msg); + } + + chunk = readChunk(); + } + + inflateEnd(&stream); + if ((size_t)stream.total_out != dataSize()) { + errx( + EX_DATAERR, "%s: expected data size %zu, found %zu", + path, dataSize(), (size_t)stream.total_out + ); + } + + if (verbose) { + fprintf( + stderr, "%s: deflate size %zu\n", path, (size_t)stream.total_in + ); + } +} + +static void writeData(void) { + if (verbose) fprintf(stderr, "%s: data size %zu\n", path, dataSize()); + + uLong size = compressBound(dataSize()); + uint8_t *deflate = malloc(size); + if (!deflate) err(EX_OSERR, "malloc"); + + int error = compress2(deflate, &size, data, dataSize(), Z_BEST_COMPRESSION); + if (error != Z_OK) errx(EX_SOFTWARE, "%s: compress2: %d", path, error); + + struct Chunk idat = { .size = size, .type = "IDAT" }; + writeChunk(idat); + writeExpect(deflate, size); + writeCrc(); + + free(deflate); + + if (verbose) fprintf(stderr, "%s: deflate size %lu\n", path, size); +} + +static void writeEnd(void) { + struct Chunk iend = { .size = 0, .type = "IEND" }; + writeChunk(iend); + writeCrc(); +} + +enum PACKED Filter { + None, + Sub, + Up, + Average, + Paeth, + FilterCount, +}; + +struct Bytes { + uint8_t x; + uint8_t a; + uint8_t b; + uint8_t c; +}; + +static uint8_t paethPredictor(struct Bytes f) { + int32_t p = (int32_t)f.a + (int32_t)f.b - (int32_t)f.c; + int32_t pa = abs(p - (int32_t)f.a); + int32_t pb = abs(p - (int32_t)f.b); + int32_t pc = abs(p - (int32_t)f.c); + if (pa <= pb && pa <= pc) return f.a; + if (pb <= pc) return f.b; + return f.c; +} + +static uint8_t recon(enum Filter type, struct Bytes f) { + switch (type) { + case None: return f.x; + case Sub: return f.x + f.a; + case Up: return f.x + f.b; + case Average: return f.x + ((uint32_t)f.a + (uint32_t)f.b) / 2; + case Paeth: return f.x + paethPredictor(f); + default: abort(); + } +} + +static uint8_t filt(enum Filter type, struct Bytes f) { + switch (type) { + case None: return f.x; + case Sub: return f.x - f.a; + case Up: return f.x - f.b; + case Average: return f.x - ((uint32_t)f.a + (uint32_t)f.b) / 2; + case Paeth: return f.x - paethPredictor(f); + default: abort(); + } +} + +static struct Line { + enum Filter type; + uint8_t data[]; +} **lines; + +static void allocLines(void) { + lines = calloc(header.height, sizeof(*lines)); + if (!lines) err(EX_OSERR, "calloc(%u, %zu)", header.height, sizeof(*lines)); +} + +static void scanlines(void) { + size_t stride = 1 + lineSize(); + for (uint32_t y = 0; y < header.height; ++y) { + lines[y] = (struct Line *)&data[y * stride]; + if (lines[y]->type >= FilterCount) { + errx(EX_DATAERR, "%s: invalid filter type %hhu", path, lines[y]->type); + } + } +} + +static struct Bytes origBytes(uint32_t y, size_t i) { + bool a = (i >= pixelSize()), b = (y > 0), c = (a && b); + return (struct Bytes) { + .x = lines[y]->data[i], + .a = a ? lines[y]->data[i - pixelSize()] : 0, + .b = b ? lines[y - 1]->data[i] : 0, + .c = c ? lines[y - 1]->data[i - pixelSize()] : 0, + }; +} + +static void reconData(void) { + for (uint32_t y = 0; y < header.height; ++y) { + for (size_t i = 0; i < lineSize(); ++i) { + lines[y]->data[i] = + recon(lines[y]->type, origBytes(y, i)); + } + lines[y]->type = None; + } +} + +static void filterData(void) { + if (header.color == Indexed || header.depth < 8) return; + for (uint32_t y = header.height - 1; y < header.height; --y) { + uint8_t filter[FilterCount][lineSize()]; + uint32_t heuristic[FilterCount] = {0}; + enum Filter minType = None; + for (enum Filter type = None; type < FilterCount; ++type) { + for (size_t i = 0; i < lineSize(); ++i) { + filter[type][i] = filt(type, origBytes(y, i)); + heuristic[type] += abs((int8_t)filter[type][i]); + } + if (heuristic[type] < heuristic[minType]) minType = type; + } + lines[y]->type = minType; + memcpy(lines[y]->data, filter[minType], lineSize()); + } +} + +static void discardAlpha(void) { + if (header.color != GrayscaleAlpha && header.color != TruecolorAlpha) return; + size_t sampleSize = header.depth / 8; + size_t colorSize = pixelSize() - sampleSize; + for (uint32_t y = 0; y < header.height; ++y) { + for (uint32_t x = 0; x < header.width; ++x) { + for (size_t i = 0; i < sampleSize; ++i) { + if (lines[y]->data[x * pixelSize() + colorSize + i] != 0xFF) return; + } + } + } + + uint8_t *ptr = data; + for (uint32_t y = 0; y < header.height; ++y) { + *ptr++ = lines[y]->type; + for (uint32_t x = 0; x < header.width; ++x) { + memmove(ptr, &lines[y]->data[x * pixelSize()], colorSize); + ptr += colorSize; + } + } + header.color = (header.color == GrayscaleAlpha) ? Grayscale : Truecolor; + scanlines(); +} + +static void discardColor(void) { + if (header.color != Truecolor && header.color != TruecolorAlpha) return; + size_t sampleSize = header.depth / 8; + for (uint32_t y = 0; y < header.height; ++y) { + for (uint32_t x = 0; x < header.width; ++x) { + uint8_t *r = &lines[y]->data[x * pixelSize()]; + uint8_t *g = r + sampleSize; + uint8_t *b = g + sampleSize; + if (0 != memcmp(r, g, sampleSize)) return; + if (0 != memcmp(g, b, sampleSize)) return; + } + } + + uint8_t *ptr = data; + for (uint32_t y = 0; y < header.height; ++y) { + *ptr++ = lines[y]->type; + for (uint32_t x = 0; x < header.width; ++x) { + uint8_t *pixel = &lines[y]->data[x * pixelSize()]; + memmove(ptr, pixel, sampleSize); + ptr += sampleSize; + if (header.color == TruecolorAlpha) { + memmove(ptr, pixel + 3 * sampleSize, sampleSize); + ptr += sampleSize; + } + } + } + header.color = (header.color == Truecolor) ? Grayscale : GrayscaleAlpha; + scanlines(); +} + +static void indexColor(void) { + if (header.color != Truecolor && header.color != TruecolorAlpha) return; + if (header.depth != 8) return; + bool alpha = (header.color == TruecolorAlpha); + for (uint32_t y = 0; y < header.height; ++y) { + for (uint32_t x = 0; x < header.width; ++x) { + if (!paletteAdd(alpha, &lines[y]->data[x * pixelSize()])) return; + } + } + transCompact(); + + uint8_t *ptr = data; + for (uint32_t y = 0; y < header.height; ++y) { + *ptr++ = lines[y]->type; + for (uint32_t x = 0; x < header.width; ++x) { + *ptr++ = paletteIndex(alpha, &lines[y]->data[x * pixelSize()]); + } + } + header.color = Indexed; + scanlines(); +} + +static void reduceDepth8(void) { + if (header.color != Grayscale && header.color != Indexed) return; + if (header.depth != 8) return; + if (header.color == Grayscale) { + for (uint32_t y = 0; y < header.height; ++y) { + for (size_t i = 0; i < lineSize(); ++i) { + uint8_t a = lines[y]->data[i]; + if ((a >> 4) != (a & 0x0F)) return; + } + } + } else if (palette.len > 16) { + return; + } + + uint8_t *ptr = data; + for (uint32_t y = 0; y < header.height; ++y) { + *ptr++ = lines[y]->type; + for (size_t i = 0; i < lineSize(); i += 2) { + uint8_t iByte = lines[y]->data[i]; + uint8_t jByte = (i + 1 < lineSize()) ? lines[y]->data[i + 1] : 0; + uint8_t a = iByte & 0x0F; + uint8_t b = jByte & 0x0F; + *ptr++ = a << 4 | b; + } + } + header.depth = 4; + scanlines(); +} + +static void reduceDepth4(void) { + if (header.depth != 4) return; + if (header.color == Grayscale) { + for (uint32_t y = 0; y < header.height; ++y) { + for (size_t i = 0; i < lineSize(); ++i) { + uint8_t a = lines[y]->data[i] >> 4; + uint8_t b = lines[y]->data[i] & 0x0F; + if ((a >> 2) != (a & 0x03)) return; + if ((b >> 2) != (b & 0x03)) return; + } + } + } else if (palette.len > 4) { + return; + } + + uint8_t *ptr = data; + for (uint32_t y = 0; y < header.height; ++y) { + *ptr++ = lines[y]->type; + for (size_t i = 0; i < lineSize(); i += 2) { + uint8_t iByte = lines[y]->data[i]; + uint8_t jByte = (i + 1 < lineSize()) ? lines[y]->data[i + 1] : 0; + uint8_t a = iByte >> 4 & 0x03, b = iByte & 0x03; + uint8_t c = jByte >> 4 & 0x03, d = jByte & 0x03; + *ptr++ = a << 6 | b << 4 | c << 2 | d; + } + } + header.depth = 2; + scanlines(); +} + +static void reduceDepth2(void) { + if (header.depth != 2) return; + if (header.color == Grayscale) { + for (uint32_t y = 0; y < header.height; ++y) { + for (size_t i = 0; i < lineSize(); ++i) { + uint8_t a = lines[y]->data[i] >> 6; + uint8_t b = lines[y]->data[i] >> 4 & 0x03; + uint8_t c = lines[y]->data[i] >> 2 & 0x03; + uint8_t d = lines[y]->data[i] & 0x03; + if ((a >> 1) != (a & 0x01)) return; + if ((b >> 1) != (b & 0x01)) return; + if ((c >> 1) != (c & 0x01)) return; + if ((d >> 1) != (d & 0x01)) return; + } + } + } else if (palette.len > 2) { + return; + } + + uint8_t *ptr = data; + for (uint32_t y = 0; y < header.height; ++y) { + *ptr++ = lines[y]->type; + for (size_t i = 0; i < lineSize(); i += 2) { + uint8_t iByte = lines[y]->data[i]; + uint8_t jByte = (i + 1 < lineSize()) ? lines[y]->data[i + 1] : 0; + uint8_t a = iByte >> 6 & 0x01, b = iByte >> 4 & 0x01; + uint8_t c = iByte >> 2 & 0x01, d = iByte & 0x01; + uint8_t e = jByte >> 6 & 0x01, f = jByte >> 4 & 0x01; + uint8_t g = jByte >> 2 & 0x01, h = jByte & 0x01; + *ptr++ = a << 7 | b << 6 | c << 5 | d << 4 | e << 3 | f << 2 | g << 1 | h; + } + } + header.depth = 1; + scanlines(); +} + +static void reduceDepth(void) { + reduceDepth8(); + reduceDepth4(); + reduceDepth2(); +} + +static void optimize(const char *inPath, const char *outPath) { + if (inPath) { + path = inPath; + file = fopen(path, "r"); + if (!file) err(EX_NOINPUT, "%s", path); + } else { + path = "(stdin)"; + file = stdin; + } + + readSignature(); + struct Chunk ihdr = readChunk(); + if (0 != memcmp(ihdr.type, "IHDR", 4)) { + errx(EX_DATAERR, "%s: expected IHDR, found %s", path, typeStr(ihdr)); + } + readHeader(ihdr); + if (header.interlace != Progressive) { + errx( + EX_CONFIG, "%s: unsupported interlace method %hhu", + path, header.interlace + ); + } + + paletteClear(); + allocData(); + for (;;) { + struct Chunk chunk = readChunk(); + if (0 == memcmp(chunk.type, "PLTE", 4)) { + readPalette(chunk); + } else if (0 == memcmp(chunk.type, "tRNS", 4)) { + readTrans(chunk); + } else if (0 == memcmp(chunk.type, "IDAT", 4)) { + readData(chunk); + } else if (0 != memcmp(chunk.type, "IEND", 4)) { + skipChunk(chunk); + } else { + break; + } + } + + fclose(file); + + allocLines(); + scanlines(); + reconData(); + + discardAlpha(); + discardColor(); + indexColor(); + reduceDepth(); + filterData(); + free(lines); + + if (outPath) { + path = outPath; + file = fopen(path, "w"); + if (!file) err(EX_CANTCREAT, "%s", path); + } else { + path = "(stdout)"; + file = stdout; + } + + writeSignature(); + writeHeader(); + if (header.color == Indexed) { + writePalette(); + if (trans.len) writeTrans(); + } + writeData(); + writeEnd(); + free(data); + + int error = fclose(file); + if (error) err(EX_IOERR, "%s", path); +} + +int main(int argc, char *argv[]) { + bool stdio = false; + char *output = NULL; + + int opt; + while (0 < (opt = getopt(argc, argv, "co:v"))) { + switch (opt) { + break; case 'c': stdio = true; + break; case 'o': output = optarg; + break; case 'v': verbose = true; + break; default: return EX_USAGE; + } + } + + if (argc - optind == 1 && (output || stdio)) { + optimize(argv[optind], output); + } else if (optind < argc) { + for (int i = optind; i < argc; ++i) { + optimize(argv[i], argv[i]); + } + } else { + optimize(NULL, output); + } + + return EX_OK; +} |