1 files changed, 357 insertions, 0 deletions
diff --git a/src/util/str.h b/src/util/str.h
new file mode 100644
index 000000000..588e6fc22
--- /dev/null
+++ b/src/util/str.h
@@ -0,0 +1,357 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_str_h__
+#define INCLUDE_str_h__
+
+#include "git2_util.h"
+
+struct git_str {
+	char *ptr;
+	size_t asize;
+	size_t size;
+};
+
+typedef enum {
+	GIT_STR_BOM_NONE = 0,
+	GIT_STR_BOM_UTF8 = 1,
+	GIT_STR_BOM_UTF16_LE = 2,
+	GIT_STR_BOM_UTF16_BE = 3,
+	GIT_STR_BOM_UTF32_LE = 4,
+	GIT_STR_BOM_UTF32_BE = 5
+} git_str_bom_t;
+
+typedef struct {
+	git_str_bom_t bom; /* BOM found at head of text */
+	unsigned int nul, cr, lf, crlf; /* NUL, CR, LF and CRLF counts */
+	unsigned int printable, nonprintable; /* These are just approximations! */
+} git_str_text_stats;
+
+extern char git_str__initstr[];
+extern char git_str__oom[];
+
+/* Use to initialize string buffer structure when git_str is on stack */
+#define GIT_STR_INIT { git_str__initstr, 0, 0 }
+
+/**
+ * Static initializer for git_str from static string buffer
+ */
+#define GIT_STR_INIT_CONST(str, len) { (char *)(str), 0, (size_t)(len) }
+
+GIT_INLINE(bool) git_str_is_allocated(const git_str *str)
+{
+	return (str->ptr != NULL && str->asize > 0);
+}
+
+/**
+ * Initialize a git_str structure.
+ *
+ * For the cases where GIT_STR_INIT cannot be used to do static
+ * initialization.
+ */
+extern int git_str_init(git_str *str, size_t initial_size);
+
+extern void git_str_dispose(git_str *str);
+
+/**
+ * Resize the string buffer allocation to make more space.
+ *
+ * This will attempt to grow the string buffer to accommodate the target
+ * size.  The bstring buffer's `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 str 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
+ */
+int git_str_grow(git_str *str, size_t target_size);
+
+/**
+ * Resize the buffer allocation to make more space.
+ *
+ * This will attempt to grow the string buffer to accommodate the
+ * additional size.  It is similar to `git_str_grow`, but performs the
+ * new size calculation, checking for overflow.
+ *
+ * Like `git_str_grow`, if this is a user-supplied string buffer,
+ * this will allocate a new string uffer.
+ */
+extern int git_str_grow_by(git_str *str, size_t additional_size);
+
+/**
+ * Attempt to grow the buffer to hold at least `target_size` bytes.
+ *
+ * If the allocation fails, this will return an error.  If `mark_oom` is
+ * true, this will mark the string buffer as invalid for future
+ * operations; if false, existing string buffer content will be preserved,
+ * but calling code must handle that string buffer was not expanded.  If
+ * `preserve_external` is true, then any existing data pointed to be
+ * `ptr` even if `asize` is zero will be copied into the newly allocated
+ * string buffer.
+ */
+extern int git_str_try_grow(
+	git_str *str, size_t target_size, bool mark_oom);
+
+extern void git_str_swap(git_str *str_a, git_str *str_b);
+extern char *git_str_detach(git_str *str);
+extern int git_str_attach(git_str *str, char *ptr, size_t asize);
+
+/* Populates a `git_str` where the contents are not "owned" by the string
+ * buffer, and calls to `git_str_dispose` will not free the given str.
+ */
+extern void git_str_attach_notowned(
+	git_str *str, const char *ptr, size_t size);
+
+/**
+ * Test if there have been any reallocation failures with this git_str.
+ *
+ * Any function that writes to a git_str can fail due to memory allocation
+ * issues.  If one fails, the git_str will be marked with an OOM error and
+ * further calls to modify the string buffer will fail.  Check
+ * git_str_oom() at the end of your sequence and it will be true if you
+ * ran out of memory at any point with that string buffer.
+ *
+ * @return false if no error, true if allocation error
+ */
+GIT_INLINE(bool) git_str_oom(const git_str *str)
+{
+	return (str->ptr == git_str__oom);
+}
+
+/*
+ * Functions below that return int value error codes will return 0 on
+ * success or -1 on failure (which generally means an allocation failed).
+ * Using a git_str where the allocation has failed with result in -1 from
+ * all further calls using that string buffer.  As a result, you can
+ * ignore the return code of these functions and call them in a series
+ * then just call git_str_oom at the end.
+ */
+
+int git_str_set(git_str *str, const void *data, size_t datalen);
+
+int git_str_sets(git_str *str, const char *string);
+int git_str_putc(git_str *str, char c);
+int git_str_putcn(git_str *str, char c, size_t len);
+int git_str_put(git_str *str, const char *data, size_t len);
+int git_str_puts(git_str *str, const char *string);
+int git_str_printf(git_str *str, const char *format, ...) GIT_FORMAT_PRINTF(2, 3);
+int git_str_vprintf(git_str *str, const char *format, va_list ap);
+void git_str_clear(git_str *str);
+void git_str_consume_bytes(git_str *str, size_t len);
+void git_str_consume(git_str *str, const char *end);
+void git_str_truncate(git_str *str, size_t len);
+void git_str_shorten(git_str *str, size_t amount);
+void git_str_truncate_at_char(git_str *path, char separator);
+void git_str_rtruncate_at_char(git_str *path, char separator);
+
+/** General join with separator */
+int git_str_join_n(git_str *str, char separator, int len, ...);
+/** Fast join of two strings - first may legally point into `str` data */
+int git_str_join(git_str *str, char separator, const char *str_a, const char *str_b);
+/** Fast join of three strings - cannot reference `str` data */
+int git_str_join3(git_str *str, char separator, const char *str_a, const char *str_b, const char *str_c);
+
+/**
+ * Join two strings as paths, inserting a slash between as needed.
+ * @return 0 on success, -1 on failure
+ */
+GIT_INLINE(int) git_str_joinpath(git_str *str, const char *a, const char *b)
+{
+	return git_str_join(str, '/', a, b);
+}
+
+GIT_INLINE(const char *) git_str_cstr(const git_str *str)
+{
+	return str->ptr;
+}
+
+GIT_INLINE(size_t) git_str_len(const git_str *str)
+{
+	return str->size;
+}
+
+int git_str_copy_cstr(char *data, size_t datasize, const git_str *str);
+
+#define git_str_PUTS(str, cstr) git_str_put(str, cstr, sizeof(cstr) - 1)
+
+GIT_INLINE(ssize_t) git_str_rfind_next(const git_str *str, char ch)
+{
+	ssize_t idx = (ssize_t)str->size - 1;
+	while (idx >= 0 && str->ptr[idx] == ch) idx--;
+	while (idx >= 0 && str->ptr[idx] != ch) idx--;
+	return idx;
+}
+
+GIT_INLINE(ssize_t) git_str_rfind(const git_str *str, char ch)
+{
+	ssize_t idx = (ssize_t)str->size - 1;
+	while (idx >= 0 && str->ptr[idx] != ch) idx--;
+	return idx;
+}
+
+GIT_INLINE(ssize_t) git_str_find(const git_str *str, char ch)
+{
+	void *found = memchr(str->ptr, ch, str->size);
+	return found ? (ssize_t)((const char *)found - str->ptr) : -1;
+}
+
+/* Remove whitespace from the end of the string buffer */
+void git_str_rtrim(git_str *str);
+
+int git_str_cmp(const git_str *a, const git_str *b);
+
+/* Quote and unquote a string buffer as specified in
+ * http://marc.info/?l=git&m=112927316408690&w=2
+ */
+int git_str_quote(git_str *str);
+int git_str_unquote(git_str *str);
+
+/* Write data as a hex string */
+int git_str_encode_hexstr(git_str *str, const char *data, size_t len);
+
+/* Write data as base64 encoded in string buffer */
+int git_str_encode_base64(git_str *str, const char *data, size_t len);
+/* Decode the given bas64 and write the result to the string buffer */
+int git_str_decode_base64(git_str *str, const char *base64, size_t len);
+
+/* Write data as "base85" encoded in string buffer */
+int git_str_encode_base85(git_str *str, const char *data, size_t len);
+/* Decode the given "base85" and write the result to the string buffer */
+int git_str_decode_base85(git_str *str, const char *base64, size_t len, size_t output_len);
+
+/*
+ * Decode the given percent-encoded string and write the result to the
+ * string buffer.
+ */
+int git_str_decode_percent(git_str *str, const char *encoded, size_t len);
+
+/*
+ * Insert, remove or replace a portion of the string buffer.
+ *
+ * @param str The string buffer to work with
+ *
+ * @param where The location in the string buffer where the transformation
+ * should be applied.
+ *
+ * @param nb_to_remove The number of chars to be removed. 0 to not
+ * remove any character in the string buffer.
+ *
+ * @param data A pointer to the data which should be inserted.
+ *
+ * @param nb_to_insert The number of chars to be inserted. 0 to not
+ * insert any character from the string buffer.
+ *
+ * @return 0 or an error code.
+ */
+int git_str_splice(
+	git_str *str,
+	size_t where,
+	size_t nb_to_remove,
+	const char *data,
+	size_t nb_to_insert);
+
+/**
+ * Append string to string buffer, prefixing each character from
+ * `esc_chars` with `esc_with` string.
+ *
+ * @param str String buffer to append data to
+ * @param string String to escape and append
+ * @param esc_chars Characters to be escaped
+ * @param esc_with String to insert in from of each found character
+ * @return 0 on success, <0 on failure (probably allocation problem)
+ */
+extern int git_str_puts_escaped(
+	git_str *str,
+	const char *string,
+	const char *esc_chars,
+	const char *esc_with);
+
+/**
+ * Append string escaping characters that are regex special
+ */
+GIT_INLINE(int) git_str_puts_escape_regex(git_str *str, const char *string)
+{
+	return git_str_puts_escaped(str, string, "^.[]$()|*+?{}\\", "\\");
+}
+
+/**
+ * Unescape all characters in a string buffer in place
+ *
+ * I.e. remove backslashes
+ */
+extern void git_str_unescape(git_str *str);
+
+/**
+ * Replace all \r\n with \n.
+ *
+ * @return 0 on success, -1 on memory error
+ */
+extern int git_str_crlf_to_lf(git_str *tgt, const git_str *src);
+
+/**
+ * Replace all \n with \r\n. Does not modify existing \r\n.
+ *
+ * @return 0 on success, -1 on memory error
+ */
+extern int git_str_lf_to_crlf(git_str *tgt, const git_str *src);
+
+/**
+ * Fill string buffer with the common prefix of a array of strings
+ *
+ * String buffer will be set to empty if there is no common prefix
+ */
+extern int git_str_common_prefix(git_str *buf, char *const *const strings, size_t count);
+
+/**
+ * Check if a string buffer begins with a UTF BOM
+ *
+ * @param bom Set to the type of BOM detected or GIT_BOM_NONE
+ * @param str String buffer in which to check the first bytes for a BOM
+ * @return Number of bytes of BOM data (or 0 if no BOM found)
+ */
+extern int git_str_detect_bom(git_str_bom_t *bom, const git_str *str);
+
+/**
+ * Gather stats for a piece of text
+ *
+ * Fill the `stats` structure with counts of unreadable characters, carriage
+ * returns, etc, so it can be used in heuristics.  This automatically skips
+ * a trailing EOF (\032 character).  Also it will look for a BOM at the
+ * start of the text and can be told to skip that as well.
+ *
+ * @param stats Structure to be filled in
+ * @param str Text to process
+ * @param skip_bom Exclude leading BOM from stats if true
+ * @return Does the string buffer heuristically look like binary data
+ */
+extern bool git_str_gather_text_stats(
+	git_str_text_stats *stats, const git_str *str, bool skip_bom);
+
+/**
+* Check quickly if string buffer looks like it contains binary data
+*
+* @param str string buffer to check
+* @return 1 if string buffer looks like non-text data
+*/
+int git_str_is_binary(const git_str *str);
+
+/**
+* Check quickly if buffer contains a NUL byte
+*
+* @param str string buffer to check
+* @return 1 if string buffer contains a NUL byte
+*/
+int git_str_contains_nul(const git_str *str);
+
+#endif