summary refs log tree commit diff
path: root/bin
diff options
context:
space:
mode:
authorJune McEnroe <june@causal.agency>2018-02-28 13:04:58 -0500
committerJune McEnroe <june@causal.agency>2018-02-28 13:04:58 -0500
commite49ebeddc437bd5d147bd6e84af1a952872634e5 (patch)
treebaf4410616c2311220e00288e46de65d25a03578 /bin
parentSet Light terminal white to Gruvbox fg3 (diff)
downloadsrc-e49ebeddc437bd5d147bd6e84af1a952872634e5.tar.gz
src-e49ebeddc437bd5d147bd6e84af1a952872634e5.zip
Clean up pngo
Big difference is changing lines from an array of structs containing
pointers into data to an array of pointers to structs pointing directly
into data.
Diffstat (limited to 'bin')
-rw-r--r--bin/pngo.c201
1 files changed, 104 insertions, 97 deletions
diff --git a/bin/pngo.c b/bin/pngo.c
index a0ecfd0f..80721547 100644
--- a/bin/pngo.c
+++ b/bin/pngo.c
@@ -27,7 +27,7 @@
 #include <zlib.h>
 
 #define PACKED __attribute__((packed))
-#define BYTE_PAIR(a, b) ((uint16_t)(a) << 8 | (uint16_t)(b))
+#define PAIR(a, b) ((uint16_t)(a) << 8 | (uint16_t)(b))
 
 #define CRC_INIT (crc32(0, Z_NULL, 0))
 
@@ -69,6 +69,10 @@ struct PACKED Chunk {
     char type[4];
 };
 
+static bool ancillary(struct Chunk chunk) {
+    return chunk.type[0] & 0x20;
+}
+
 static const char *typeStr(struct Chunk chunk) {
     static char buf[5];
     memcpy(buf, chunk.type, 4);
@@ -83,6 +87,11 @@ static struct Chunk readChunk(void) {
     return chunk;
 }
 
+static void skipChunk(struct Chunk chunk) {
+    int error = fseek(file, chunk.size + 4, SEEK_CUR);
+    if (error) err(EX_IOERR, "%s", path);
+}
+
 static void writeChunk(struct Chunk chunk) {
     chunk.size = htonl(chunk.size);
     writeExpect(&chunk, sizeof(chunk));
@@ -96,7 +105,7 @@ static void readCrc(void) {
     found = ntohl(found);
     if (found != expected) {
         errx(
-            EX_DATAERR, "%s: expected CRC32 %08x, found %08x",
+            EX_DATAERR, "%s: expected CRC32 %08X, found %08X",
             path, expected, found
         );
     }
@@ -107,19 +116,17 @@ static void writeCrc(void) {
     writeExpect(&net, sizeof(net));
 }
 
-enum PACKED Color {
-    GRAYSCALE       = 0,
-    TRUECOLOR       = 2,
-    INDEXED         = 3,
-    GRAYSCALE_ALPHA = 4,
-    TRUECOLOR_ALPHA = 6,
-};
-
 static struct PACKED {
     uint32_t width;
     uint32_t height;
     uint8_t depth;
-    enum Color color;
+    enum PACKED {
+        GRAYSCALE       = 0,
+        TRUECOLOR       = 2,
+        INDEXED         = 3,
+        GRAYSCALE_ALPHA = 4,
+        TRUECOLOR_ALPHA = 6,
+    } color;
     enum PACKED { DEFLATE } compression;
     enum PACKED { ADAPTIVE } filter;
     enum PACKED { PROGRESSIVE, ADAM7 } interlace;
@@ -159,12 +166,23 @@ static void readHeader(void) {
 
     if (!header.width) errx(EX_DATAERR, "%s: invalid width 0", path);
     if (!header.height) errx(EX_DATAERR, "%s: invalid height 0", path);
-    switch (BYTE_PAIR(header.color, header.depth)) {
-        case 0x0001: case 0x0002: case 0x0004: case 0x0008: case 0x0010: break;
-        case 0x0208: case 0x0210:                                        break;
-        case 0x0301: case 0x0302: case 0x0304: case 0x0308:              break;
-        case 0x0408: case 0x0410:                                        break;
-        case 0x0608: case 0x0610:                                        break;
+    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(GRAYSCALE_ALPHA, 8):
+        case PAIR(GRAYSCALE_ALPHA, 16):
+        case PAIR(TRUECOLOR_ALPHA, 8):
+        case PAIR(TRUECOLOR_ALPHA, 16):
+            break;
         default:
             errx(
                 EX_DATAERR, "%s: invalid color type %hhu and bit depth %hhu",
@@ -186,7 +204,7 @@ static void readHeader(void) {
 }
 
 static void writeHeader(void) {
-    struct Chunk ihdr = { .size = sizeof(header), .type = { 'I', 'H', 'D', 'R' } };
+    struct Chunk ihdr = { .size = sizeof(header), .type = "IHDR" };
     writeChunk(ihdr);
     header.width = htonl(header.width);
     header.height = htonl(header.height);
@@ -223,7 +241,9 @@ static void readPalette(void) {
         chunk = readChunk();
         if (0 == memcmp(chunk.type, "PLTE", 4)) {
             break;
-        } else if (!(chunk.type[0] & 0x20)) {
+        } else if (ancillary(chunk)) {
+            skipChunk(chunk);
+        } else {
             errx(
                 EX_DATAERR, "%s: expected PLTE chunk, found %s",
                 path, typeStr(chunk)
@@ -240,7 +260,7 @@ static void readPalette(void) {
 }
 
 static void writePalette(void) {
-    struct Chunk plte = { .size = 3 * palette.len, .type = { 'P', 'L', 'T', 'E' } };
+    struct Chunk plte = { .size = 3 * palette.len, .type = "PLTE" };
     writeChunk(plte);
     writeExpect(palette.entries, plte.size);
     writeCrc();
@@ -260,33 +280,30 @@ static void readData(void) {
 
     for (;;) {
         struct Chunk chunk = readChunk();
-        if (0 == memcmp(chunk.type, "IEND", 4)) {
+        if (0 == memcmp(chunk.type, "IDAT", 4)) {
+            uint8_t idat[chunk.size];
+            readExpect(idat, sizeof(idat), "image data");
+            readCrc();
+
+            stream.next_in = idat;
+            stream.avail_in = sizeof(idat);
+            int error = inflate(&stream, Z_SYNC_FLUSH);
+            if (error == Z_STREAM_END) break;
+            if (error != Z_OK) errx(EX_DATAERR, "%s: inflate: %s", path, stream.msg);
+
+        } else if (0 == memcmp(chunk.type, "IEND", 4)) {
             errx(EX_DATAERR, "%s: missing IDAT chunk", path);
-        }
-        if (0 != memcmp(chunk.type, "IDAT", 4)) {
-            if (chunk.type[0] & 0x20) {
-                int error = fseek(file, chunk.size + 4, SEEK_CUR);
-                if (error) err(EX_IOERR, "%s", path);
-                continue;
-            }
+        } else if (ancillary(chunk)) {
+            skipChunk(chunk);
+        } else {
             errx(
                 EX_CONFIG, "%s: unsupported critical chunk %s",
                 path, typeStr(chunk)
             );
         }
-
-        uint8_t idat[chunk.size];
-        readExpect(idat, sizeof(idat), "image data");
-        readCrc();
-
-        stream.next_in = idat;
-        stream.avail_in = chunk.size;
-        int error = inflate(&stream, Z_SYNC_FLUSH);
-        if (error == Z_STREAM_END) break;
-        if (error != Z_OK) errx(EX_DATAERR, "%s: inflate: %s", path, stream.msg);
     }
-    inflateEnd(&stream);
 
+    inflateEnd(&stream);
     if (stream.total_out != dataSize()) {
         errx(
             EX_DATAERR, "%s: expected data size %zu, found %lu",
@@ -301,14 +318,14 @@ static void writeData(void) {
     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 = { 'I', 'D', 'A', 'T' } };
+    struct Chunk idat = { .size = size, .type = "IDAT" };
     writeChunk(idat);
     writeExpect(deflate, size);
     writeCrc();
 }
 
 static void writeEnd(void) {
-    struct Chunk iend = { .size = 0, .type = { 'I', 'E', 'N', 'D' } };
+    struct Chunk iend = { .size = 0, .type = "IEND" };
     writeChunk(iend);
     writeCrc();
 }
@@ -361,10 +378,10 @@ static uint8_t filt(enum Filter type, struct Bytes f) {
     }
 }
 
-static struct {
-    enum Filter *type;
-    uint8_t *data;
-} *lines;
+static struct Line {
+    enum Filter type;
+    uint8_t data[];
+} **lines;
 
 static void allocLines(void) {
     lines = calloc(header.height, sizeof(*lines));
@@ -374,10 +391,9 @@ static void allocLines(void) {
 static void scanlines(void) {
     size_t stride = 1 + lineSize();
     for (uint32_t y = 0; y < header.height; ++y) {
-        lines[y].type = &data[y * stride];
-        lines[y].data = &data[y * stride + 1];
-        if (*lines[y].type >= FILTER_COUNT) {
-            errx(EX_DATAERR, "%s: invalid filter type %hhu", path, *lines[y].type);
+        lines[y] = (struct Line *)&data[y * stride];
+        if (lines[y]->type >= FILTER_COUNT) {
+            errx(EX_DATAERR, "%s: invalid filter type %hhu", path, lines[y]->type);
         }
     }
 }
@@ -387,35 +403,28 @@ static struct Bytes origBytes(uint32_t y, size_t i) {
     if (!pixelSize) pixelSize = 1;
     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,
+        .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]->data[i] =
+                recon(lines[y]->type, origBytes(y, i));
         }
-        *lines[y].type = NONE;
+        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) {
-        if (header.color == INDEXED || header.depth < 8) {
-            *lines[y].type = NONE;
-            for (size_t i = lineSize() - 1; i < lineSize(); --i) {
-                lines[y].data[i] = filt(NONE, origBytes(y, i));
-            }
-            continue;
-        }
-
         uint8_t filter[FILTER_COUNT][lineSize()];
-        uint32_t heuristic[FILTER_COUNT] = { 0 };
+        uint32_t heuristic[FILTER_COUNT] = {0};
         enum Filter minType = NONE;
         for (enum Filter type = NONE; type < FILTER_COUNT; ++type) {
             for (size_t i = 0; i < lineSize(); ++i) {
@@ -424,8 +433,8 @@ static void filterData(void) {
             }
             if (heuristic[type] < heuristic[minType]) minType = type;
         }
-        *lines[y].type = minType;
-        memcpy(lines[y].data, filter[minType], lineSize());
+        lines[y]->type = minType;
+        memcpy(lines[y]->data, filter[minType], lineSize());
     }
 }
 
@@ -437,16 +446,16 @@ static void discardAlpha(void) {
     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;
+                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;
+        *ptr++ = lines[y]->type;
         for (uint32_t x = 0; x < header.width; ++x) {
-            memcpy(ptr, &lines[y].data[x * pixelSize], colorSize);
+            memcpy(ptr, &lines[y]->data[x * pixelSize], colorSize);
             ptr += colorSize;
         }
     }
@@ -460,7 +469,7 @@ static void discardColor(void) {
     size_t pixelSize = sampleSize * (header.color == TRUECOLOR ? 3 : 4);
     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 *r = &lines[y]->data[x * pixelSize];
             uint8_t *g = r + sampleSize;
             uint8_t *b = g + sampleSize;
             if (0 != memcmp(r, g, sampleSize)) return;
@@ -470,9 +479,9 @@ static void discardColor(void) {
 
     uint8_t *ptr = data;
     for (uint32_t y = 0; y < header.height; ++y) {
-        *ptr++ = *lines[y].type;
+        *ptr++ = lines[y]->type;
         for (uint32_t x = 0; x < header.width; ++x) {
-            uint8_t *pixel = &lines[y].data[x * pixelSize];
+            uint8_t *pixel = &lines[y]->data[x * pixelSize];
             memcpy(ptr, pixel, sampleSize);
             ptr += sampleSize;
             if (header.color == TRUECOLOR_ALPHA) {
@@ -489,15 +498,15 @@ static void indexColor(void) {
     if (header.color != TRUECOLOR || header.depth != 8) return;
     for (uint32_t y = 0; y < header.height; ++y) {
         for (uint32_t x = 0; x < header.width; ++x) {
-            if (!paletteAdd(&lines[y].data[x * 3])) return;
+            if (!paletteAdd(&lines[y]->data[x * 3])) return;
         }
     }
 
     uint8_t *ptr = data;
     for (uint32_t y = 0; y < header.height; ++y) {
-        *ptr++ = *lines[y].type;
+        *ptr++ = lines[y]->type;
         for (uint32_t x = 0; x < header.width; ++x) {
-            *ptr++ = paletteIndex(&lines[y].data[x * 3]);
+            *ptr++ = paletteIndex(&lines[y]->data[x * 3]);
         }
     }
     header.color = INDEXED;
@@ -510,7 +519,7 @@ static void reduceDepth8(void) {
     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];
+                uint8_t a = lines[y]->data[i];
                 if ((a >> 4) != (a & 0x0F)) return;
             }
         }
@@ -520,10 +529,10 @@ static void reduceDepth8(void) {
 
     uint8_t *ptr = data;
     for (uint32_t y = 0; y < header.height; ++y) {
-        *ptr++ = *lines[y].type;
+        *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 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;
@@ -538,8 +547,8 @@ static void reduceDepth4(void) {
     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;
+                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;
             }
@@ -550,10 +559,10 @@ static void reduceDepth4(void) {
 
     uint8_t *ptr = data;
     for (uint32_t y = 0; y < header.height; ++y) {
-        *ptr++ = *lines[y].type;
+        *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 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;
@@ -568,10 +577,10 @@ static void reduceDepth2(void) {
     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;
+                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;
@@ -584,10 +593,10 @@ static void reduceDepth2(void) {
 
     uint8_t *ptr = data;
     for (uint32_t y = 0; y < header.height; ++y) {
-        *ptr++ = *lines[y].type;
+        *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 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;
@@ -626,9 +635,7 @@ static void optimize(const char *inPath, const char *outPath) {
     if (header.color == INDEXED) readPalette();
     allocData();
     readData();
-
-    int error = fclose(file);
-    if (error) err(EX_IOERR, "%s", path);
+    fclose(file);
 
     allocLines();
     scanlines();
@@ -654,10 +661,10 @@ static void optimize(const char *inPath, const char *outPath) {
     writeHeader();
     if (header.color == INDEXED) writePalette();
     writeData();
-    free(data);
     writeEnd();
+    free(data);
 
-    error = fclose(file);
+    int error = fclose(file);
     if (error) err(EX_IOERR, "%s", path);
 }