1 /*
2 * io_manager.c --- the I/O manager abstraction
3 */
4
5 #include "config.h"
6 #include <stdio.h>
7 #include <string.h>
8 #if HAVE_UNISTD_H
9 #include <unistd.h>
10 #endif
11 #include <fcntl.h>
12 #include <time.h>
13 #if HAVE_SYS_STAT_H
14 #include <sys/stat.h>
15 #endif
16 #if HAVE_SYS_TYPES_H
17 #include <sys/types.h>
18 #endif
19
20 #include "ext2_fs.h"
21 #include "ext2fs.h"
22
io_channel_set_options(io_channel channel,const char * opts)23 errcode_t io_channel_set_options(io_channel channel, const char *opts)
24 {
25 errcode_t retval = 0;
26 char *next, *ptr, *options, *arg;
27
28 EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
29
30 if (!opts)
31 return 0;
32
33 if (!channel->manager->set_option)
34 return EXT2_ET_INVALID_ARGUMENT;
35
36 options = malloc(strlen(opts)+1);
37 if (!options)
38 return EXT2_ET_NO_MEMORY;
39 strcpy(options, opts);
40 ptr = options;
41
42 while (ptr && *ptr) {
43 next = strchr(ptr, '&');
44 if (next)
45 *next++ = 0;
46
47 arg = strchr(ptr, '=');
48 if (arg)
49 *arg++ = 0;
50
51 retval = (channel->manager->set_option)(channel, ptr, arg);
52 if (retval)
53 break;
54 ptr = next;
55 }
56 free(options);
57 return retval;
58 }
59
io_channel_write_byte(io_channel channel,unsigned long offset,int count,const void * data)60 errcode_t io_channel_write_byte(io_channel channel, unsigned long offset,
61 int count, const void *data)
62 {
63 EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
64
65 if (channel->manager->write_byte)
66 return channel->manager->write_byte(channel, offset,
67 count, data);
68
69 return EXT2_ET_UNIMPLEMENTED;
70 }
71
io_channel_read_blk64(io_channel channel,unsigned long long block,int count,void * data)72 errcode_t io_channel_read_blk64(io_channel channel, unsigned long long block,
73 int count, void *data)
74 {
75 EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
76
77 if (channel->manager->read_blk64)
78 return (channel->manager->read_blk64)(channel, block,
79 count, data);
80
81 if ((block >> 32) != 0)
82 return EXT2_ET_IO_CHANNEL_NO_SUPPORT_64;
83
84 return (channel->manager->read_blk)(channel, (unsigned long) block,
85 count, data);
86 }
87
io_channel_write_blk64(io_channel channel,unsigned long long block,int count,const void * data)88 errcode_t io_channel_write_blk64(io_channel channel, unsigned long long block,
89 int count, const void *data)
90 {
91 EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
92
93 if (channel->manager->write_blk64)
94 return (channel->manager->write_blk64)(channel, block,
95 count, data);
96
97 if ((block >> 32) != 0)
98 return EXT2_ET_IO_CHANNEL_NO_SUPPORT_64;
99
100 return (channel->manager->write_blk)(channel, (unsigned long) block,
101 count, data);
102 }
103
io_channel_discard(io_channel channel,unsigned long long block,unsigned long long count)104 errcode_t io_channel_discard(io_channel channel, unsigned long long block,
105 unsigned long long count)
106 {
107 EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
108
109 if (channel->manager->discard)
110 return (channel->manager->discard)(channel, block, count);
111
112 return EXT2_ET_UNIMPLEMENTED;
113 }
114
io_channel_zeroout(io_channel channel,unsigned long long block,unsigned long long count)115 errcode_t io_channel_zeroout(io_channel channel, unsigned long long block,
116 unsigned long long count)
117 {
118 EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
119
120 if (channel->manager->zeroout)
121 return (channel->manager->zeroout)(channel, block, count);
122
123 return EXT2_ET_UNIMPLEMENTED;
124 }
125
io_channel_alloc_buf(io_channel io,int count,void * ptr)126 errcode_t io_channel_alloc_buf(io_channel io, int count, void *ptr)
127 {
128 size_t size;
129
130 if (count == 0)
131 size = io->block_size;
132 else if (count > 0)
133 size = io->block_size * count;
134 else
135 size = -count;
136
137 if (io->align > 0) {
138 if ((unsigned) io->align > size)
139 size = io->align;
140 return ext2fs_get_memalign(size, io->align, ptr);
141 } else
142 return ext2fs_get_mem(size, ptr);
143 }
144
io_channel_cache_readahead(io_channel io,unsigned long long block,unsigned long long count)145 errcode_t io_channel_cache_readahead(io_channel io, unsigned long long block,
146 unsigned long long count)
147 {
148 if (!io->manager->cache_readahead)
149 return EXT2_ET_OP_NOT_SUPPORTED;
150
151 return io->manager->cache_readahead(io, block, count);
152 }
153