1 /*
2 * Copyright (C) 1999-2004 Etymon Systems, Inc.
3 *
4 * Authors: Nassib Nassar
5 */
6
7 #include <stdlib.h>
8 #include <sys/types.h>
9 #include <stdio.h>
10 #include <string.h>
11 #include "linbuf.h"
12 #include "util.h"
13
14 #define LINBUFSEGSIZE ((size_t) 1000000000)
15
16 static size_t bufsize;
17 static FILE *fbuf;
18 static unsigned char **linbuf;
19 static size_t *linbuflen;
20 static int linbufn;
21
createbuf()22 static int createbuf()
23 {
24 int x;
25 size_t z;
26
27 linbufn = (bufsize / LINBUFSEGSIZE) + 1;
28 linbuf = (unsigned char **) malloc(linbufn * sizeof (unsigned char *));
29 if (!linbuf)
30 return aferr(AFEMEM);
31 linbuflen = (size_t *) malloc(linbufn * sizeof (size_t));
32 if (!linbuflen)
33 return aferr(AFEMEM);
34 for (z = bufsize, x = 0; z > 0; z -= LINBUFSEGSIZE, x++) {
35 linbuf[x] = (unsigned char *) malloc( linbuflen[x] = (
36 z < LINBUFSEGSIZE ? z : LINBUFSEGSIZE) );
37 if (!linbuf[x])
38 return aferr(AFEMEM);
39 if (z < LINBUFSEGSIZE)
40 break;
41 }
42
43 return 0;
44 }
45
fillbuf()46 static int fillbuf()
47 {
48 int x;
49
50 if (fseeko(fbuf, 0, SEEK_SET) < 0)
51 return aferr(AFEDBIO);
52 for (x = 0; x < linbufn; x++) {
53 if (fread(linbuf[x], 1, linbuflen[x], fbuf) < linbuflen[x])
54 return aferr(AFEDBIO);
55 }
56
57 return 0;
58 }
59
aflinbuf(FILE * f,int mem)60 int aflinbuf(FILE *f, int mem)
61 {
62 off_t fsize;
63
64 afgetfsize(f, &fsize);
65 bufsize = ((size_t) mem) * 1048576;
66 /* printf("aflinbuf: %i %lu %lu\n", mem, (unsigned long) fsize,
67 (unsigned long) bufsize);*/
68 bufsize = fsize < bufsize ? fsize : bufsize;
69 fbuf = f;
70 if (createbuf() < 0)
71 return -1;
72 if (fillbuf() < 0)
73 return -1;
74
75 return 0;
76 }
77
bufcpy(unsigned char * ptr,off_t offset,size_t size)78 void bufcpy(unsigned char *ptr, off_t offset, size_t size)
79 {
80 int x;
81 int b, bx;
82
83 b = offset / LINBUFSEGSIZE;
84 bx = offset % LINBUFSEGSIZE;
85 for (x = 0; x < size; x++) {
86 ptr[x] = linbuf[b][bx];
87 if (++bx >= linbuflen[b]) {
88 b++;
89 bx = 0;
90 }
91 }
92 }
93
aflinread(void * ptr,off_t offset,size_t size)94 int aflinread(void *ptr, off_t offset, size_t size)
95 {
96 if ((offset + size) <= bufsize) {
97 /* printf("."); fflush(stdout);*/
98 bufcpy((unsigned char *)ptr, offset, size);
99 } else {
100 /* printf("\n%lu %lu %lu\n", (unsigned long) offset,
101 (unsigned long) size,
102 (unsigned long) bufsize);*/
103 /* printf("*"); fflush(stdout);*/
104 fseeko(fbuf, offset, SEEK_SET);
105 if (fread(ptr, 1, size, fbuf) < size)
106 return aferr(AFEDBIO);
107 }
108
109 return 0;
110 }
111