summaryrefslogtreecommitdiffstatshomepage
path: root/src/emu/ioprocs.c
blob: 7413aa8756f48bdffba7632377ddb0f939cd8d2e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
#include <stdio.h>
#include <string.h>
#include "ioprocs.h"


/*********************************************************************
    ioprocs implementation on stdio
*********************************************************************/

static void stdio_closeproc(void *file)
{
	fclose((FILE*)file);
}

static int stdio_seekproc(void *file, INT64 offset, int whence)
{
	return fseek((FILE*)file, (long) offset, whence);
}

static size_t stdio_readproc(void *file, void *buffer, size_t length)
{
	return fread(buffer, 1, length, (FILE*)file);
}

static size_t stdio_writeproc(void *file, const void *buffer, size_t length)
{
	return fwrite(buffer, 1, length, (FILE*)file);
}

static UINT64 stdio_filesizeproc(void *file)
{
	long l, sz;
	l = ftell((FILE*)file);
	if (fseek((FILE*)file, 0, SEEK_END))
		return (size_t) -1;
	sz = ftell((FILE*)file);
	if (fseek((FILE*)file, l, SEEK_SET))
		return (size_t) -1;
	return (size_t) sz;
}

const struct io_procs stdio_ioprocs =
{
	stdio_closeproc,
	stdio_seekproc,
	stdio_readproc,
	stdio_writeproc,
	stdio_filesizeproc
};

const struct io_procs stdio_ioprocs_noclose =
{
	NULL,
	stdio_seekproc,
	stdio_readproc,
	stdio_writeproc,
	stdio_filesizeproc
};



/*********************************************************************
    calls for accessing generic IO
*********************************************************************/

static void io_generic_seek(struct io_generic *generic, UINT64 offset)
{
	generic->procs->seekproc(generic->file, offset, SEEK_SET);
}



void io_generic_close(struct io_generic *generic)
{
	if (generic->procs->closeproc)
		generic->procs->closeproc(generic->file);
}



void io_generic_read(struct io_generic *generic, void *buffer, UINT64 offset, size_t length)
{
	UINT64 size;
	size_t bytes_read;

	size = io_generic_size(generic);
	if (size <= offset)
	{
		bytes_read = 0;
	}
	else
	{
		io_generic_seek(generic, offset);
		bytes_read = generic->procs->readproc(generic->file, buffer, length);
	}
	memset(((UINT8 *) buffer) + bytes_read, generic->filler, length - bytes_read);
}



void io_generic_write(struct io_generic *generic, const void *buffer, UINT64 offset, size_t length)
{
	UINT64 filler_size = 0;
	char filler_buffer[1024];
	size_t bytes_to_write;
	UINT64 size;

	if (offset > 0x29c50)
	{
		offset = offset;
	}

	size = io_generic_size(generic);

	if (size < offset)
	{
		filler_size = offset - size;
		offset = size;
	}

	io_generic_seek(generic, offset);

	if (filler_size)
	{
		memset(filler_buffer, generic->filler, sizeof(buffer));
		do
		{
			bytes_to_write = (filler_size > sizeof(filler_buffer)) ? sizeof(filler_buffer) : (size_t) filler_size;
			generic->procs->writeproc(generic->file, filler_buffer, bytes_to_write);
			filler_size -= bytes_to_write;
		}
		while(filler_size > 0);
	}

	if (length > 0)
		generic->procs->writeproc(generic->file, buffer, length);
}



void io_generic_write_filler(struct io_generic *generic, UINT8 filler, UINT64 offset, size_t length)
{
	UINT8 buffer[512];
	size_t this_length;

	memset(buffer, filler, MIN(length, sizeof(buffer)));

	while(length > 0)
	{
		this_length = MIN(length, sizeof(buffer));
		io_generic_write(generic, buffer, offset, this_length);
		offset += this_length;
		length -= this_length;
	}
}



UINT64 io_generic_size(struct io_generic *generic)
{
	return generic->procs->filesizeproc(generic->file);
}