*
* Sometimes libgit2 wants to return an allocated data buffer to the
* caller and have the caller take responsibility for freeing that memory.
- * This can be awkward if the caller does not have easy access to the same
- * allocation functions that libgit2 is using. In those cases, libgit2
- * will fill in a `git_buf` and the caller can use `git_buf_dispose()` to
- * release it when they are done.
+ * To make ownership clear in these cases, libgit2 uses `git_buf` to
+ * return this data. Callers should use `git_buf_dispose()` to release
+ * the memory when they are done.
*
- * A `git_buf` may also be used for the caller to pass in a reference to
- * a block of memory they hold. In this case, libgit2 will not resize or
- * free the memory, but will read from it as needed.
- *
- * Some APIs may occasionally do something slightly unusual with a buffer,
- * such as setting `ptr` to a value that was passed in by the user. In
- * those cases, the behavior will be clearly documented by the API.
+ * A `git_buf` contains a pointer to a NUL-terminated C string, and
+ * the length of the string (not including the NUL terminator).
*/
typedef struct {
/**
- * The buffer contents.
- *
- * `ptr` points to the start of the allocated memory. If it is NULL,
- * then the `git_buf` is considered empty and libgit2 will feel free
- * to overwrite it with new data.
+ * The buffer contents. `ptr` points to the start of the buffer
+ * being returned. The buffer's length (in bytes) is specified
+ * by the `size` member of the structure, and contains a NUL
+ * terminator at position `(size + 1)`.
*/
- char *ptr;
+ char *ptr;
/**
- * `asize` holds the known total amount of allocated memory if the `ptr`
- * was allocated by libgit2. It may be larger than `size`. If `ptr`
- * was not allocated by libgit2 and should not be resized and/or freed,
- * then `asize` will be set to zero.
+ * This field is reserved and unused.
*/
- size_t asize;
+ size_t reserved;
/**
- * `size` holds the size (in bytes) of the data that is actually used.
+ * The length (in bytes) of the buffer pointed to by `ptr`,
+ * not including a NUL terminator.
*/
size_t size;
} git_buf;
/**
- * Static initializer for git_buf from static buffer
+ * Use to initialize a `git_buf` before passing it to a function that
+ * will populate it.
*/
-#define GIT_BUF_INIT_CONST(STR,LEN) { (char *)(STR), 0, (size_t)(LEN) }
+#define GIT_BUF_INIT { NULL, 0, 0 }
/**
* Free the memory referred to by the git_buf.
*
* Note that this does not free the `git_buf` itself, just the memory
- * pointed to by `buffer->ptr`. This will not free the memory if it looks
- * like it was not allocated internally, but it will clear the buffer back
- * to the empty state.
+ * pointed to by `buffer->ptr`.
*
* @param buffer The buffer to deallocate
*/
GIT_EXTERN(void) git_buf_dispose(git_buf *buffer);
-/**
- * Resize the buffer allocation to make more space.
- *
- * This will attempt to grow the buffer to accommodate the target size.
- *
- * If the buffer refers to memory that was not allocated by libgit2 (i.e.
- * the `asize` field is zero), then `ptr` will be replaced with a newly
- * allocated block of data. Be careful so that memory allocated by the
- * caller is not lost. As a special variant, if you pass `target_size` as
- * 0 and the memory is not allocated by libgit2, this will allocate a new
- * buffer of size `size` and copy the external data into it.
- *
- * Currently, this will never shrink a buffer, only expand it.
- *
- * If the allocation fails, this will return an error and the buffer will be
- * marked as invalid for future operations, invaliding the contents.
- *
- * @param buffer The buffer to be resized; may or may not be allocated yet
- * @param target_size The desired available size
- * @return 0 on success, -1 on allocation failure
- */
-GIT_EXTERN(int) git_buf_grow(git_buf *buffer, size_t target_size);
-
-/**
- * Set buffer to a copy of some raw data.
- *
- * @param buffer The buffer to set
- * @param data The data to copy into the buffer
- * @param datalen The length of the data to copy into the buffer
- * @return 0 on success, -1 on allocation failure
- */
-GIT_EXTERN(int) git_buf_set(
- git_buf *buffer, const void *data, size_t datalen);
-
-/**
-* Check quickly if buffer looks like it contains binary data
-*
-* @param buf Buffer to check
-* @return 1 if buffer looks like non-text data
-*/
-GIT_EXTERN(int) git_buf_is_binary(const git_buf *buf);
-
-/**
-* Check quickly if buffer contains a NUL byte
-*
-* @param buf Buffer to check
-* @return 1 if buffer contains a NUL byte
-*/
-GIT_EXTERN(int) git_buf_contains_nul(const git_buf *buf);
-
GIT_END_DECL
/** @} */
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