lavf: add directory listing API

API allows protocol implementations to provide API that
allows to list directory content.
API is similar to POSIX opendir/readdir/closedir.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 83 insertions, 1 deletions

diff --git a/libavformat/avio.h b/libavformat/avio.h
index 8fc7e27d4e..bbd482a52e 100644
--- a/libavformat/avio.h
+++ b/libavformat/avio.h
@@ -34,7 +34,6 @@
 
 #include "libavformat/version.h"
 
-
 #define AVIO_SEEKABLE_NORMAL 0x0001 /**< Seeking works like for a local file */
 
 /**
@@ -54,6 +53,47 @@ typedef struct AVIOInterruptCB {
 } AVIOInterruptCB;
 
 /**
+ * Directory entry types.
+ */
+enum AVIODirEntryType {
+    AVIO_ENTRY_UNKNOWN,
+    AVIO_ENTRY_BLOCK_DEVICE,
+    AVIO_ENTRY_CHARACTER_DEVICE,
+    AVIO_ENTRY_DIRECTORY,
+    AVIO_ENTRY_NAMED_PIPE,
+    AVIO_ENTRY_SYMBOLIC_LINK,
+    AVIO_ENTRY_SOCKET,
+    AVIO_ENTRY_FILE
+};
+
+/**
+ * Describes single entry of the directory.
+ *
+ * Only name and type fields are guaranteed be set.
+ * Rest of fields are protocol or/and platform dependent and might be unknown.
+ */
+typedef struct AVIODirEntry {
+    char *name;                           /**< Filename */
+    int type;                             /**< Type of the entry */
+    int utf8;                             /**< Set to 1 when name is encoded with UTF-8, 0 otherwise.
+                                               Name can be encoded with UTF-8 eventhough 0 is set. */
+    int64_t size;                         /**< File size in bytes, -1 if unknown. */
+    int64_t modification_timestamp;       /**< Time of last modification in microseconds since unix
+                                               epoch, -1 if unknown. */
+    int64_t access_timestamp;             /**< Time of last access in microseconds since unix epoch,
+                                               -1 if unknown. */
+    int64_t status_change_timestamp;      /**< Time of last status change in microseconds since unix
+                                               epoch, -1 if unknown. */
+    int64_t user_id;                      /**< User ID of owner, -1 if unknown. */
+    int64_t group_id;                     /**< Group ID of owner, -1 if unknown. */
+    int64_t filemode;                     /**< Unix file mode, -1 if unknown. */
+} AVIODirEntry;
+
+typedef struct AVIODirContext {
+    struct URLContext *url_context;
+} AVIODirContext;
+
+/**
  * Bytestream IO Context.
  * New fields can be added to the end with minor version bumps.
  * Removal, reordering and changes to existing fields require a major
@@ -181,6 +221,48 @@ const char *avio_find_protocol_name(const char *url);
 int avio_check(const char *url, int flags);
 
 /**
+ * Open directory for reading.
+ *
+ * @param s       directory read context. Pointer to a NULL pointer must be passed.
+ * @param url     directory to be listed.
+ * @param options A dictionary filled with protocol-private options. On return
+ *                this parameter will be destroyed and replaced with a dictionary
+ *                containing options that were not found. May be NULL.
+ * @return >=0 on success or negative on error.
+ */
+int avio_open_dir(AVIODirContext **s, const char *url, AVDictionary **options);
+
+/**
+ * Get next directory entry.
+ *
+ * Returned entry must be freed with avio_free_directory_entry(). In particular
+ * it may outlive AVIODirContext.
+ *
+ * @param s         directory read context.
+ * @param[out] next next entry or NULL when no more entries.
+ * @return >=0 on success or negative on error.
+ */
+int avio_read_dir(AVIODirContext *s, AVIODirEntry **next);
+
+/**
+ * Close directory.
+ *
+ * @note Entries created using avio_read_dir() are not deleted and must be
+ * freeded with avio_free_directory_entry().
+ *
+ * @param s         directory read context.
+ * @return >=0 on success or negative on error.
+ */
+int avio_close_dir(AVIODirContext **s);
+
+/**
+ * Free entry allocated by avio_read_dir().
+ *
+ * @param entry entry to be freed.
+ */
+void avio_free_directory_entry(AVIODirEntry **entry);
+
+/**
  * Allocate and initialize an AVIOContext for buffered I/O. It must be later
  * freed with av_free().
  *