src/buf_text.h

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7 #ifndef INCLUDE_buf_text_h__
   8 #define INCLUDE_buf_text_h__
   9
  10 #include "buffer.h"
  11
  12 typedef enum {
  13         GIT_BOM_NONE = 0,
  14         GIT_BOM_UTF8 = 1,
  15         GIT_BOM_UTF16_LE = 2,
  16         GIT_BOM_UTF16_BE = 3,
  17         GIT_BOM_UTF32_LE = 4,
  18         GIT_BOM_UTF32_BE = 5
  19 } git_bom_t;
  20
  21 typedef struct {
  22         git_bom_t bom; /* BOM found at head of text */
  23         unsigned int nul, cr, lf, crlf; /* NUL, CR, LF and CRLF counts */
  24         unsigned int printable, nonprintable; /* These are just approximations! */
  25 } git_buf_text_stats;
  26
  27 /**
  28  * Append string to buffer, prefixing each character from `esc_chars` with
  29  * `esc_with` string.
  30  *
  31  * @param buf Buffer to append data to
  32  * @param string String to escape and append
  33  * @param esc_chars Characters to be escaped
  34  * @param esc_with String to insert in from of each found character
  35  * @return 0 on success, <0 on failure (probably allocation problem)
  36  */
  37 extern int git_buf_text_puts_escaped(
  38         git_buf *buf,
  39         const char *string,
  40         const char *esc_chars,
  41         const char *esc_with);
  42
  43 /**
  44  * Append string escaping characters that are regex special
  45  */
  46 GIT_INLINE(int) git_buf_text_puts_escape_regex(git_buf *buf, const char *string)
  47 {
  48         return git_buf_text_puts_escaped(buf, string, "^.[]$()|*+?{}\\", "\\");
  49 }
  50
  51 /**
  52  * Unescape all characters in a buffer in place
  53  *
  54  * I.e. remove backslashes
  55  */
  56 extern void git_buf_text_unescape(git_buf *buf);
  57
  58 /**
  59  * Replace all \r\n with \n (or do nothing if no \r\n are found)
  60  *
  61  * @return 0 on success, GIT_ENOTFOUND if no \r\n, -1 on memory error
  62  */
  63 extern int git_buf_text_crlf_to_lf(git_buf *tgt, const git_buf *src);
  64
  65 /**
  66  * Replace all \n with \r\n (or do nothing if no \n are found)
  67  *
  68  * @return 0 on success, GIT_ENOTFOUND if no \n, -1 on memory error
  69  */
  70 extern int git_buf_text_lf_to_crlf(git_buf *tgt, const git_buf *src);
  71
  72 /**
  73  * Fill buffer with the common prefix of a array of strings
  74  *
  75  * Buffer will be set to empty if there is no common prefix
  76  */
  77 extern int git_buf_text_common_prefix(git_buf *buf, const git_strarray *strs);
  78
  79 /**
  80  * Check quickly if buffer looks like it contains binary data
  81  *
  82  * @param buf Buffer to check
  83  * @return true if buffer looks like non-text data
  84  */
  85 extern bool git_buf_text_is_binary(const git_buf *buf);
  86
  87 /**
  88  * Check quickly if buffer contains a NUL byte
  89  *
  90  * @param buf Buffer to check
  91  * @return true if buffer contains a NUL byte
  92  */
  93 extern bool git_buf_text_contains_nul(const git_buf *buf);
  94
  95 /**
  96  * Check if a buffer begins with a UTF BOM
  97  *
  98  * @param bom Set to the type of BOM detected or GIT_BOM_NONE
  99  * @param buf Buffer in which to check the first bytes for a BOM
 100  * @param offset Offset into buffer to look for BOM
 101  * @return Number of bytes of BOM data (or 0 if no BOM found)
 102  */
 103 extern int git_buf_text_detect_bom(
 104         git_bom_t *bom, const git_buf *buf, size_t offset);
 105
 106 /**
 107  * Gather stats for a piece of text
 108  *
 109  * Fill the `stats` structure with counts of unreadable characters, carriage
 110  * returns, etc, so it can be used in heuristics.  This automatically skips
 111  * a trailing EOF (\032 character).  Also it will look for a BOM at the
 112  * start of the text and can be told to skip that as well.
 113  *
 114  * @param stats Structure to be filled in
 115  * @param buf Text to process
 116  * @param skip_bom Exclude leading BOM from stats if true
 117  * @return Does the buffer heuristically look like binary data
 118  */
 119 extern bool git_buf_text_gather_stats(
 120         git_buf_text_stats *stats, const git_buf *buf, bool skip_bom);
 121
 122 #endif