Add libexif to deps/third_party.

libexif/sources/libexif/exif-entry.h

+/*! \file exif-entry.h
+ *  \brief Handling EXIF entries
+ */
+/*
+ * Copyright (c) 2001 Lutz Mueller <lutz@users.sourceforge.net>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details. 
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301  USA.
+ */
+
+#ifndef __EXIF_ENTRY_H__
+#define __EXIF_ENTRY_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/*! Data found in one EXIF tag.
+ * The #exif_entry_get_value function can provide access to the
+ * formatted contents, or the struct members can be used directly to
+ * access the raw contents.
+ */
+typedef struct _ExifEntry        ExifEntry;
+typedef struct _ExifEntryPrivate ExifEntryPrivate;
+
+#include <libexif/exif-content.h>
+#include <libexif/exif-format.h>
+#include <libexif/exif-mem.h>
+
+/*! Data found in one EXIF tag */
+struct _ExifEntry {
+        /*! EXIF tag for this entry */
+        ExifTag tag;
+        
+        /*! Type of data in this entry */
+        ExifFormat format;
+
+        /*! Number of elements in the array, if this is an array entry.
+         * Contains 1 for non-array data types. */
+        unsigned long components;
+
+        /*! Pointer to the raw EXIF data for this entry. It is allocated
+         * by #exif_entry_initialize and is NULL beforehand. Data contained
+         * here may be manipulated using the functions in exif-utils.h */
+        unsigned char *data;
+
+        /*! Number of bytes in the buffer at \c data. This must be no less
+         * than exif_format_get_size(format)*components */
+        unsigned int size;
+
+        /*! #ExifContent containing this entry. 
+         * \see exif_entry_get_ifd */
+        ExifContent *parent;
+
+        /*! Internal data to be used by libexif itself */
+        ExifEntryPrivate *priv;
+};
+
+/* Lifecycle */
+
+/*! Reserve memory for and initialize a new #ExifEntry.
+ * No memory is allocated for the \c data element of the returned #ExifEntry.
+ *
+ * \return new allocated #ExifEntry, or NULL on error
+ *
+ * \see exif_entry_new_mem, exif_entry_unref
+ */
+ExifEntry  *exif_entry_new     (void);
+
+/*! Reserve memory for and initialize new #ExifEntry using the specified
+ * memory allocator.
+ * No memory is allocated for the \c data element of the returned #ExifEntry.
+ *
+ * \return new allocated #ExifEntry, or NULL on error
+ *
+ * \see exif_entry_new, exif_entry_unref
+ */
+ExifEntry  *exif_entry_new_mem (ExifMem *);
+
+/*! Increase reference counter for #ExifEntry.
+ *
+ * \param[in] entry #ExifEntry
+ *
+ * \see exif_entry_unref
+ */
+void        exif_entry_ref     (ExifEntry *entry);
+
+/*! Decrease reference counter for #ExifEntry.
+ * When the reference count drops to zero, free the entry.
+ *
+ * \param[in] entry #ExifEntry
+ */
+void        exif_entry_unref   (ExifEntry *entry);
+
+/*! Actually free the #ExifEntry.
+ *
+ * \deprecated Should not be called directly. Use #exif_entry_ref and
+ *             #exif_entry_unref instead.
+ *
+ * \param[in] entry EXIF entry
+ */
+void        exif_entry_free  (ExifEntry *entry);
+
+/*! Initialize an empty #ExifEntry with default data in the correct format
+ * for the given tag. If the entry is already initialized, this function
+ * does nothing.
+ * This call allocates memory for the \c data element of the given #ExifEntry.
+ * That memory is freed at the same time as the #ExifEntry.
+ *
+ * \param[out] e entry to initialize
+ * \param[in] tag tag number to initialize as
+ */
+void        exif_entry_initialize (ExifEntry *e, ExifTag tag);
+
+/*! Fix the type or format of the given EXIF entry to bring it into spec.
+ * If the data for this EXIF tag is in of the wrong type or is in an invalid
+ * format according to the EXIF specification, then it is converted to make it
+ * valid. This may involve, for example, converting an EXIF_FORMAT_LONG into a
+ * EXIF_FORMAT_SHORT. If the tag is unknown, its value is untouched.
+ *
+ * \note Unfortunately, some conversions are to a type with a more restricted
+ * range, which could have the side effect that the converted data becomes
+ * invalid. This is unlikely as the range of each tag in the standard is
+ * designed to encompass all likely data.
+ *
+ * \param[in,out] entry EXIF entry
+ */
+void        exif_entry_fix        (ExifEntry *entry);
+
+
+/* For your convenience */
+
+/*! Return a localized textual representation of the value of the EXIF entry.
+ * This is meant for display to the user. The format of each tag is subject
+ * to change between locales and in newer versions of libexif.  Users who
+ * require the tag data in an unambiguous form should access the data members
+ * of the #ExifEntry structure directly.
+ *
+ * \warning The character set of the returned string may be in
+ *          the encoding of the current locale or the native encoding
+ *          of the camera.
+ * \bug     The EXIF_TAG_XP_* tags are currently always returned in UTF-8,
+ *          regardless of locale, and code points above U+FFFF are not
+ *          supported.
+ *
+ * \param[in] entry EXIF entry
+ * \param[out] val buffer in which to store value
+ * \param[in] maxlen length of the buffer val
+ * \return val pointer
+ */
+const char *exif_entry_get_value (ExifEntry *entry, char *val,
+                                  unsigned int maxlen);
+
+/*! Dump text representation of #ExifEntry to stdout.
+ * This is intended for diagnostic purposes only.
+ *
+ * \param[in] entry EXIF tag data
+ * \param[in] indent how many levels deep to indent the data
+ */
+void        exif_entry_dump      (ExifEntry *entry, unsigned int indent);
+
+/*! Return the IFD number of the given #ExifEntry
+ *
+ * \param[in] e an #ExifEntry*
+ * \return #ExifIfd, or #EXIF_IFD_COUNT on error
+ */
+#define exif_entry_get_ifd(e) ((e)?exif_content_get_ifd((e)->parent):EXIF_IFD_COUNT)
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* __EXIF_ENTRY_H__ */