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authorscuri <scuri>2008-10-17 06:10:15 +0000
committerscuri <scuri>2008-10-17 06:10:15 +0000
commit5a422aba704c375a307a902bafe658342e209906 (patch)
tree5005011e086bb863d8fb587ad3319bbec59b2447 /src/libexif/exif-loader.c
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'src/libexif/exif-loader.c')
-rw-r--r--src/libexif/exif-loader.c349
1 files changed, 349 insertions, 0 deletions
diff --git a/src/libexif/exif-loader.c b/src/libexif/exif-loader.c
new file mode 100644
index 0000000..d6eba7d
--- /dev/null
+++ b/src/libexif/exif-loader.c
@@ -0,0 +1,349 @@
+#include <config.h>
+
+#include <libexif/exif-loader.h>
+#include <libexif/i18n.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+#undef JPEG_MARKER_SOI
+#define JPEG_MARKER_SOI 0xd8
+#undef JPEG_MARKER_APP0
+#define JPEG_MARKER_APP0 0xe0
+#undef JPEG_MARKER_APP1
+#define JPEG_MARKER_APP1 0xe1
+#undef JPEG_MARKER_APP13
+#define JPEG_MARKER_APP13 0xed
+#undef JPEG_MARKER_COM
+#define JPEG_MARKER_COM 0xfe
+
+typedef enum {
+ EL_READ = 0,
+ EL_READ_SIZE_BYTE_24,
+ EL_READ_SIZE_BYTE_16,
+ EL_READ_SIZE_BYTE_08,
+ EL_READ_SIZE_BYTE_00,
+ EL_SKIP_BYTES,
+ EL_EXIF_FOUND,
+} ExifLoaderState;
+
+typedef enum {
+ EL_DATA_FORMAT_UNKNOWN,
+ EL_DATA_FORMAT_EXIF,
+ EL_DATA_FORMAT_JPEG,
+ EL_DATA_FORMAT_FUJI_RAW
+} ExifLoaderDataFormat;
+
+struct _ExifLoader {
+ ExifLoaderState state;
+ ExifLoaderDataFormat data_format;
+
+ /* Small buffer used for detection of format */
+ unsigned char b[12];
+ unsigned char b_len;
+
+ unsigned int size;
+ unsigned char *buf;
+ unsigned int bytes_read;
+
+ unsigned int ref_count;
+
+ ExifLog *log;
+ ExifMem *mem;
+};
+
+static const unsigned char ExifHeader[] = {0x45, 0x78, 0x69, 0x66, 0x00, 0x00};
+
+static void *
+exif_loader_alloc (ExifLoader *l, unsigned int i)
+{
+ void *d;
+
+ if (!l || !i) return NULL;
+
+ d = exif_mem_alloc (l->mem, i);
+ if (d) return d;
+
+ EXIF_LOG_NO_MEMORY (l->log, "ExifLog", i);
+ return NULL;
+}
+
+#undef MIN
+#define MIN(a, b) (((a) < (b)) ? (a) : (b))
+
+void
+exif_loader_write_file (ExifLoader *l, const char *path)
+{
+ FILE *f;
+ int size;
+ unsigned char data[1024];
+
+ if (!l) return;
+
+ f = fopen (path, "rb");
+ if (!f) {
+ exif_log (l->log, EXIF_LOG_CODE_NONE, "ExifLoader",
+ _("The file '%s' could not be opened."), path);
+ return;
+ }
+ while (1) {
+ size = fread (data, 1, sizeof (data), f);
+ if (size <= 0) break;
+ if (!exif_loader_write (l, data, size)) break;
+ }
+ fclose (f);
+}
+
+static unsigned int
+exif_loader_copy (ExifLoader *eld, unsigned char *buf, unsigned int len)
+{
+ if (!eld || (len && !buf) || (eld->bytes_read >= eld->size)) return 0;
+
+ /* If needed, allocate the buffer. */
+ if (!eld->buf) eld->buf = exif_loader_alloc (eld, eld->size);
+ if (!eld->buf) return 0;
+
+ /* Copy memory */
+ len = MIN (len, eld->size - eld->bytes_read);
+ memcpy (eld->buf + eld->bytes_read, buf, len);
+ eld->bytes_read += len;
+
+ return (eld->bytes_read >= eld->size) ? 0 : 1;
+}
+
+unsigned char
+exif_loader_write (ExifLoader *eld, unsigned char *buf, unsigned int len)
+{
+ unsigned int i;
+
+ if (!eld || (len && !buf)) return 0;
+
+ switch (eld->state) {
+ case EL_EXIF_FOUND:
+ return exif_loader_copy (eld, buf, len);
+ case EL_SKIP_BYTES:
+ if (eld->size > len) { eld->size -= len; return 1; }
+ len -= eld->size;
+ buf += eld->size;
+ eld->size = 0;
+ eld->b_len = 0;
+ switch (eld->data_format) {
+ case EL_DATA_FORMAT_FUJI_RAW:
+ eld->state = EL_READ_SIZE_BYTE_24;
+ break;
+ default:
+ eld->state = EL_READ;
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ exif_log (eld->log, EXIF_LOG_CODE_DEBUG, "ExifLoader",
+ "Scanning %i byte(s) of data...", len);
+
+ /*
+ * First fill the small buffer. Only continue if the buffer
+ * is filled. Note that EXIF data contains at least 12 bytes.
+ */
+ i = MIN (len, sizeof (eld->b) - eld->b_len);
+ if (i) {
+ memcpy (&eld->b[eld->b_len], buf, i);
+ eld->b_len += i;
+ if (eld->b_len < sizeof (eld->b)) return 1;
+ buf += i;
+ len -= i;
+ }
+
+ switch (eld->data_format) {
+ case EL_DATA_FORMAT_UNKNOWN:
+
+ /* Check the small buffer against known formats. */
+ if (!memcmp (eld->b, "FUJIFILM", 8)) {
+
+ /* Skip to byte 84. There is another offset there. */
+ eld->data_format = EL_DATA_FORMAT_FUJI_RAW;
+ eld->size = 84;
+ eld->state = EL_SKIP_BYTES;
+ eld->size = 84;
+
+ } else if (!memcmp (eld->b + 2, ExifHeader, sizeof (ExifHeader))) {
+
+ /* Read the size (2 bytes). */
+ eld->data_format = EL_DATA_FORMAT_EXIF;
+ eld->state = EL_READ_SIZE_BYTE_08;
+ }
+ default:
+ break;
+ }
+
+ for (i = 0; i < sizeof (eld->b); i++)
+ switch (eld->state) {
+ case EL_EXIF_FOUND:
+ if (!exif_loader_copy (eld, eld->b + i,
+ sizeof (eld->b) - i)) return 0;
+ return exif_loader_copy (eld, buf, len);
+ case EL_SKIP_BYTES:
+ eld->size--;
+ if (!eld->size) eld->state = EL_READ;
+ break;
+
+ case EL_READ_SIZE_BYTE_24:
+ eld->size |= eld->b[i] << 24;
+ eld->state = EL_READ_SIZE_BYTE_16;
+ break;
+ case EL_READ_SIZE_BYTE_16:
+ eld->size |= eld->b[i] << 16;
+ eld->state = EL_READ_SIZE_BYTE_08;
+ break;
+ case EL_READ_SIZE_BYTE_08:
+ eld->size |= eld->b[i] << 8;
+ eld->state = EL_READ_SIZE_BYTE_00;
+ break;
+ case EL_READ_SIZE_BYTE_00:
+ eld->size |= eld->b[i] << 0;
+ switch (eld->data_format) {
+ case EL_DATA_FORMAT_JPEG:
+ eld->state = EL_SKIP_BYTES;
+ eld->size -= 2;
+ break;
+ case EL_DATA_FORMAT_FUJI_RAW:
+ eld->data_format = EL_DATA_FORMAT_EXIF;
+ eld->state = EL_SKIP_BYTES;
+ eld->size -= 86;
+ break;
+ case EL_DATA_FORMAT_EXIF:
+ eld->state = EL_EXIF_FOUND;
+ break;
+ default:
+ break;
+ }
+ break;
+
+ default:
+ switch (eld->b[i]) {
+ case JPEG_MARKER_APP1:
+ eld->data_format = EL_DATA_FORMAT_EXIF;
+ eld->size = 0;
+ eld->state = EL_READ_SIZE_BYTE_08;
+ break;
+ case JPEG_MARKER_APP0:
+ case JPEG_MARKER_APP13:
+ case JPEG_MARKER_COM:
+ eld->data_format = EL_DATA_FORMAT_JPEG;
+ eld->size = 0;
+ eld->state = EL_READ_SIZE_BYTE_08;
+ break;
+ case 0xff:
+ case JPEG_MARKER_SOI:
+ break;
+ default:
+ exif_log (eld->log,
+ EXIF_LOG_CODE_CORRUPT_DATA,
+ "ExifLoader", _("The data supplied "
+ "does not seem to contain "
+ "EXIF data."));
+ exif_loader_reset (eld);
+ return 0;
+ }
+ }
+
+ /*
+ * If we reach this point, the buffer has not been big enough
+ * to read all data we need. Fill it with new data.
+ */
+ eld->b_len = 0;
+ return exif_loader_write (eld, buf, len);
+}
+
+ExifLoader *
+exif_loader_new (void)
+{
+ ExifMem *mem = exif_mem_new_default ();
+ ExifLoader *l = exif_loader_new_mem (mem);
+
+ exif_mem_unref (mem);
+
+ return l;
+}
+
+ExifLoader *
+exif_loader_new_mem (ExifMem *mem)
+{
+ ExifLoader *loader;
+
+ if (!mem) return NULL;
+
+ loader = exif_mem_alloc (mem, sizeof (ExifLoader));
+ if (!loader) return NULL;
+ loader->ref_count = 1;
+
+ loader->mem = mem;
+ exif_mem_ref (mem);
+
+ return loader;
+}
+
+void
+exif_loader_ref (ExifLoader *loader)
+{
+ if (loader) loader->ref_count++;
+}
+
+static void
+exif_loader_free (ExifLoader *loader)
+{
+ ExifMem *mem;
+
+ if (!loader) return;
+
+ mem = loader->mem;
+ exif_loader_reset (loader);
+ exif_mem_free (mem, loader);
+ exif_mem_unref (mem);
+}
+
+void
+exif_loader_unref (ExifLoader *loader)
+{
+ if (!loader) return;
+ if (!--loader->ref_count)
+ exif_loader_free (loader);
+}
+
+void
+exif_loader_reset (ExifLoader *loader)
+{
+ if (!loader) return;
+ exif_mem_free (loader->mem, loader->buf); loader->buf = NULL;
+ loader->size = 0;
+ loader->bytes_read = 0;
+ loader->state = 0;
+ loader->b_len = 0;
+ loader->data_format = EL_DATA_FORMAT_UNKNOWN;
+}
+
+ExifData *
+exif_loader_get_data (ExifLoader *loader)
+{
+ ExifData *ed;
+
+ if (!loader) return NULL;
+
+ ed = exif_data_new_mem (loader->mem);
+ exif_data_log (ed, loader->log);
+ exif_data_load_data (ed, loader->buf, loader->bytes_read);
+
+ return ed;
+}
+
+void
+exif_loader_log (ExifLoader *loader, ExifLog *log)
+{
+ if (!loader) return;
+ exif_log_unref (loader->log);
+ loader->log = log;
+ exif_log_ref (log);
+}