src/filter.h

   1 /*
   2  * Copyright (C) 2009-2012 the libgit2 contributors
   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_filter_h__
   8 #define INCLUDE_filter_h__
   9
  10 #include "common.h"
  11 #include "buffer.h"
  12 #include "git2/odb.h"
  13 #include "git2/repository.h"
  14
  15 typedef struct git_filter {
  16         int (*apply)(struct git_filter *self, git_buf *dest, const git_buf *source);
  17         void (*do_free)(struct git_filter *self);
  18 } git_filter;
  19
  20 typedef enum {
  21         GIT_FILTER_TO_WORKTREE,
  22         GIT_FILTER_TO_ODB
  23 } git_filter_mode;
  24
  25 typedef enum {
  26         GIT_CRLF_GUESS = -1,
  27         GIT_CRLF_BINARY = 0,
  28         GIT_CRLF_TEXT,
  29         GIT_CRLF_INPUT,
  30         GIT_CRLF_CRLF,
  31         GIT_CRLF_AUTO,
  32 } git_crlf_t;
  33
  34 typedef struct {
  35         /* NUL, CR, LF and CRLF counts */
  36         unsigned int nul, cr, lf, crlf;
  37
  38         /* These are just approximations! */
  39         unsigned int printable, nonprintable;
  40 } git_text_stats;
  41
  42 /*
  43  * FILTER API
  44  */
  45
  46 /*
  47  * For any given path in the working directory, fill the `filters`
  48  * array with the relevant filters that need to be applied.
  49  *
  50  * Mode is either `GIT_FILTER_TO_WORKTREE` if you need to load the
  51  * filters that will be used when checking out a file to the working
  52  * directory, or `GIT_FILTER_TO_ODB` for the filters used when writing
  53  * a file to the ODB.
  54  *
  55  * @param filters Vector where to store all the loaded filters
  56  * @param repo Repository object that contains `path`
  57  * @param path Relative path of the file to be filtered
  58  * @param mode Filtering direction (WT->ODB or ODB->WT)
  59  * @return the number of filters loaded for the file (0 if the file
  60  *      doesn't need filtering), or a negative error code
  61  */
  62 extern int git_filters_load(git_vector *filters, git_repository *repo, const char *path, int mode);
  63
  64 /*
  65  * Apply one or more filters to a file.
  66  *
  67  * The file must have been loaded as a `git_buf` object. Both the `source`
  68  * and `dest` buffers are owned by the caller and must be freed once
  69  * they are no longer needed.
  70  *
  71  * NOTE: Because of the double-buffering schema, the `source` buffer that contains
  72  * the original file may be tampered once the filtering is complete. Regardless,
  73  * the `dest` buffer will always contain the final result of the filtering
  74  *
  75  * @param dest Buffer to store the result of the filtering
  76  * @param source Buffer containing the document to filter
  77  * @param filters A non-empty vector of filters as supplied by `git_filters_load`
  78  * @return 0 on success, an error code otherwise
  79  */
  80 extern int git_filters_apply(git_buf *dest, git_buf *source, git_vector *filters);
  81
  82 /*
  83  * Free the `filters` array generated by `git_filters_load`.
  84  *
  85  * Note that this frees both the array and its contents. The array will
  86  * be clean/reusable after this call.
  87  *
  88  * @param filters A filters array as supplied by `git_filters_load`
  89  */
  90 extern void git_filters_free(git_vector *filters);
  91
  92 /*
  93  * Available filters
  94  */
  95
  96 /* Strip CRLF, from Worktree to ODB */
  97 extern int git_filter_add__crlf_to_odb(git_vector *filters, git_repository *repo, const char *path);
  98
  99 /* Add CRLF, from ODB to worktree */
 100 extern int git_filter_add__crlf_to_workdir(git_vector *filters, git_repository *repo, const char *path);
 101
 102
 103 /*
 104  * PLAINTEXT API
 105  */
 106
 107 /*
 108  * Gather stats for a piece of text
 109  *
 110  * Fill the `stats` structure with information on the number of
 111  * unreadable characters, carriage returns, etc, so it can be
 112  * used in heuristics.
 113  */
 114 extern void git_text_gather_stats(git_text_stats *stats, const git_buf *text);
 115
 116 /*
 117  * Process `git_text_stats` data generated by `git_text_stat` to see
 118  * if it qualifies as a binary file
 119  */
 120 extern int git_text_is_binary(git_text_stats *stats);
 121
 122 #endif