mpv/misc/bstr.h

240 lines
8.0 KiB
C

/*
* This file is part of mpv.
*
* mpv 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 2.1 of the License, or (at your option) any later version.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef MPLAYER_BSTR_H
#define MPLAYER_BSTR_H
#include <stdint.h>
#include <stddef.h>
#include <string.h>
#include <stdbool.h>
#include <stdarg.h>
#include "mpv_talloc.h"
#include "osdep/compiler.h"
/* NOTE: 'len' is size_t, but most string-handling functions below assume
* that input size has been sanity checked and len fits in an int.
*/
typedef struct bstr {
unsigned char *start;
size_t len;
} bstr;
// If str.start is NULL, return NULL.
static inline char *bstrdup0(void *talloc_ctx, struct bstr str)
{
return talloc_strndup(talloc_ctx, (char *)str.start, str.len);
}
// Like bstrdup0(), but always return a valid C-string.
static inline char *bstrto0(void *talloc_ctx, struct bstr str)
{
return str.start ? bstrdup0(talloc_ctx, str) : talloc_strdup(talloc_ctx, "");
}
// Return start = NULL iff that is true for the original.
static inline struct bstr bstrdup(void *talloc_ctx, struct bstr str)
{
struct bstr r = { NULL, str.len };
if (str.start)
r.start = (unsigned char *)talloc_memdup(talloc_ctx, str.start, str.len);
return r;
}
#define bstr0_s(s) (struct bstr){(unsigned char *)(s), (s) ? strlen(s) : 0}
static inline struct bstr bstr0(const char *s)
{
return bstr0_s(s);
}
int bstrcmp(struct bstr str1, struct bstr str2);
int bstrcasecmp(struct bstr str1, struct bstr str2);
int bstrchr(struct bstr str, int c);
int bstrrchr(struct bstr str, int c);
int bstrspn(struct bstr str, const char *accept);
int bstrcspn(struct bstr str, const char *reject);
int bstr_find(struct bstr haystack, struct bstr needle);
struct bstr bstr_lstrip(struct bstr str);
struct bstr bstr_strip(struct bstr str);
struct bstr bstr_split(struct bstr str, const char *sep, struct bstr *rest);
bool bstr_split_tok(bstr str, const char *tok, bstr *out_left, bstr *out_right);
struct bstr bstr_splice(struct bstr str, int start, int end);
long long bstrtoll(struct bstr str, struct bstr *rest, int base);
double bstrtod(struct bstr str, struct bstr *rest);
void bstr_lower(struct bstr str);
int bstr_sscanf(struct bstr str, const char *format, ...);
// Decode a string containing hexadecimal data. All whitespace will be silently
// ignored. When successful, this allocates a new array to store the output.
bool bstr_decode_hex(void *talloc_ctx, struct bstr hex, struct bstr *out);
// Decode the UTF-8 code point at the start of the string, and return the
// character.
// After calling this function, *out_next will point to the next character.
// out_next can be NULL.
// On error, -1 is returned, and *out_next is not modified.
int bstr_decode_utf8(struct bstr str, struct bstr *out_next);
// Return the UTF-8 code point at the start of the string.
// After calling this function, *out_next will point to the next character.
// out_next can be NULL.
// On error, an empty string is returned, and *out_next is not modified.
struct bstr bstr_split_utf8(struct bstr str, struct bstr *out_next);
// Return the length of the UTF-8 sequence that starts with the given byte.
// Given a string char *s, the next UTF-8 code point is to be expected at
// s + bstr_parse_utf8_code_length(s[0])
// On error, -1 is returned. On success, it returns a value in the range [1, 4].
int bstr_parse_utf8_code_length(unsigned char b);
// Return >= 0 if the string is valid UTF-8, otherwise negative error code.
// Embedded \0 bytes are considered valid.
// This returns -N if the UTF-8 string was likely just cut-off in the middle of
// an UTF-8 sequence: -1 means 1 byte was missing, -5 5 bytes missing.
// If the string was likely not cut off, -8 is returned.
// Use (return_value > -8) to check whether the string is valid UTF-8 or valid
// but cut-off UTF-8.
int bstr_validate_utf8(struct bstr s);
// Force the input string to valid UTF-8. If invalid UTF-8 encoding is
// encountered, the invalid bytes are interpreted as Latin-1.
// Embedded \0 bytes are considered valid.
// If replacement happens, a newly allocated string is returned (with a \0
// byte added past its end for convenience). The string is allocated via
// talloc, with talloc_ctx as parent.
struct bstr bstr_sanitize_utf8_latin1(void *talloc_ctx, struct bstr s);
// Return the text before the occurrence of a character, and return it. Change
// *rest to point to the text following this character. (rest can be NULL.)
struct bstr bstr_splitchar(struct bstr str, struct bstr *rest, const char c);
// Like bstr_splitchar. Trailing newlines are not stripped.
static inline struct bstr bstr_getline(struct bstr str, struct bstr *rest)
{
return bstr_splitchar(str, rest, '\n');
}
// Strip one trailing line break. This is intended for use with bstr_getline,
// and will remove the trailing \n or \r\n sequence.
struct bstr bstr_strip_linebreaks(struct bstr str);
void bstr_xappend(void *talloc_ctx, bstr *s, bstr append);
void bstr_xappend_asprintf(void *talloc_ctx, bstr *s, const char *fmt, ...)
PRINTF_ATTRIBUTE(3, 4);
void bstr_xappend_vasprintf(void *talloc_ctx, bstr *s, const char *fmt, va_list va)
PRINTF_ATTRIBUTE(3, 0);
// If s starts/ends with prefix, return true and return the rest of the string
// in s.
bool bstr_eatstart(struct bstr *s, struct bstr prefix);
bool bstr_eatend(struct bstr *s, struct bstr prefix);
bool bstr_case_startswith(struct bstr s, struct bstr prefix);
bool bstr_case_endswith(struct bstr s, struct bstr suffix);
struct bstr bstr_strip_ext(struct bstr str);
struct bstr bstr_get_ext(struct bstr s);
static inline struct bstr bstr_cut(struct bstr str, int n)
{
if (n < 0) {
n += str.len;
if (n < 0)
n = 0;
}
if (((size_t)n) > str.len)
n = str.len;
return (struct bstr){str.start + n, str.len - n};
}
static inline bool bstr_startswith(struct bstr str, struct bstr prefix)
{
if (str.len < prefix.len)
return false;
return !memcmp(str.start, prefix.start, prefix.len);
}
static inline bool bstr_startswith0(struct bstr str, const char *prefix)
{
return bstr_startswith(str, bstr0(prefix));
}
static inline bool bstr_endswith(struct bstr str, struct bstr suffix)
{
if (str.len < suffix.len)
return false;
return !memcmp(str.start + str.len - suffix.len, suffix.start, suffix.len);
}
static inline bool bstr_endswith0(struct bstr str, const char *suffix)
{
return bstr_endswith(str, bstr0(suffix));
}
static inline int bstrcmp0(struct bstr str1, const char *str2)
{
return bstrcmp(str1, bstr0(str2));
}
static inline bool bstr_equals(struct bstr str1, struct bstr str2)
{
if (str1.len != str2.len)
return false;
return str1.start == str2.start || bstrcmp(str1, str2) == 0;
}
static inline bool bstr_equals0(struct bstr str1, const char *str2)
{
return bstr_equals(str1, bstr0(str2));
}
static inline int bstrcasecmp0(struct bstr str1, const char *str2)
{
return bstrcasecmp(str1, bstr0(str2));
}
static inline int bstr_find0(struct bstr haystack, const char *needle)
{
return bstr_find(haystack, bstr0(needle));
}
static inline bool bstr_eatstart0(struct bstr *s, const char *prefix)
{
return bstr_eatstart(s, bstr0(prefix));
}
static inline bool bstr_eatend0(struct bstr *s, const char *prefix)
{
return bstr_eatend(s, bstr0(prefix));
}
#ifdef _WIN32
int bstr_to_wchar(void *talloc_ctx, struct bstr s, wchar_t **ret);
#endif
// create a pair (not single value!) for "%.*s" printf syntax
#define BSTR_P(bstr) (int)((bstr).len), ((bstr).start ? (char*)(bstr).start : "")
#define WHITESPACE " \f\n\r\t\v"
#endif /* MPLAYER_BSTR_H */