@matheusbsbs / matheus-bagliano / commits / 79621f3e41

pack-bitmap: extract `read_bitmap()` function

The pack-bitmap machinery uses the `read_bitmap_1()` function to read a bitmap from within the mmap'd region corresponding to the .bitmap file. As as side-effect of calling this function, `read_bitmap_1()` increments the `index->map_pos` variable to reflect the number of bytes read. Extract the core of this routine to a separate function (that operates over a `const unsigned char *`, a `size_t` and a `size_t *` pointer) instead of a `struct bitmap_index *` pointer. This function (called `read_bitmap()`) is part of the pack-bitmap.h API so that it can be used within the upcoming portion of the implementation in pseduo-merge.ch. Rewrite the existing function, `read_bitmap_1()`, in terms of its more generic counterpart. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Taylor Blau committed May 23, 2024 at 17:26 UTC 79621f3e4151dfe8ef8fdb2800c59dc65f4867e6

2 files changed +17 -9

pack-bitmap.c

+15 -9

@@ -129,17 +129,13 @@ static struct ewah_bitmap *lookup_stored_bitmap(struct stored_bitmap *st)

129 return composed;

130 }

131

132 -/*

133 - * Read a bitmap from the current read position on the mmaped

134 - * index, and increase the read position accordingly

135 - */

136 -static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)

132 +struct ewah_bitmap *read_bitmap(const unsigned char *map,

133 + size_t map_size, size_t *map_pos)

134 {

135 struct ewah_bitmap *b = ewah_pool_new();

136

140 - ssize_t bitmap_size = ewah_read_mmap(b,

141 - index->map + index->map_pos,

142 - index->map_size - index->map_pos);

137 + ssize_t bitmap_size = ewah_read_mmap(b, map + *map_pos,

138 + map_size - *map_pos);

139

140 if (bitmap_size < 0) {

141 error(_("failed to load bitmap index (corrupted?)"));

@@ -147,10 +143,20 @@ static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)

143 return NULL;

144 }

145

150 - index->map_pos += bitmap_size;

146 + *map_pos += bitmap_size;

147 +

148 return b;

149 }

150

151 +/*

152 + * Read a bitmap from the current read position on the mmaped

153 + * index, and increase the read position accordingly

154 + */

155 +static struct ewah_bitmap *read_bitmap_1(struct bitmap_index *index)

156 +{

157 + return read_bitmap(index->map, index->map_size, &index->map_pos);

158 +}

159 +

160 static uint32_t bitmap_num_objects(struct bitmap_index *index)

161 {

162 if (index->midx)

pack-bitmap.h

@@ -160,4 +160,6 @@ int bitmap_is_preferred_refname(struct repository *r, const char *refname);

160

161 int verify_bitmap_files(struct repository *r);

162

163 +struct ewah_bitmap *read_bitmap(const unsigned char *map,

164 + size_t map_size, size_t *map_pos);

165 #endif