1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/ucx/memstream.c Tue Oct 09 15:02:40 2012 +0200
1.3 @@ -0,0 +1,152 @@
1.4 +#include "memstream.h"
1.5 +#include <stdarg.h>
1.6 +#include <stdlib.h>
1.7 +#include <string.h>
1.8 +
1.9 +struct _UcxMemstream {
1.10 + void *space;
1.11 + size_t pos;
1.12 + size_t length;
1.13 + _Bool autofree;
1.14 +};
1.15 +
1.16 +UcxMemstream *ucx_memopen(void* space, size_t length) {
1.17 + UcxMemstream *stream = (UcxMemstream*) malloc(sizeof(UcxMemstream));
1.18 + if (stream) {
1.19 + if (!space) {
1.20 + stream->space = malloc(length);
1.21 + if (!stream->space) {
1.22 + free(stream);
1.23 + return NULL;
1.24 + }
1.25 + memset(stream->space, 0, length);
1.26 + stream->autofree = 1;
1.27 + } else {
1.28 + stream->space = space;
1.29 + stream->autofree = 0;
1.30 + }
1.31 + stream->length = length;
1.32 +
1.33 + stream->pos = 0;
1.34 + }
1.35 +
1.36 + return stream;
1.37 +}
1.38 +
1.39 +void ucx_memclose(UcxMemstream *stream) {
1.40 + if (stream->autofree) {
1.41 + free(stream->space);
1.42 + }
1.43 + free(stream);
1.44 +}
1.45 +
1.46 +int ucx_memseek(UcxMemstream *stream, long offset, int whence) {
1.47 + size_t npos;
1.48 + switch (whence) {
1.49 + case SEEK_SET:
1.50 + npos = 0;
1.51 + break;
1.52 + case SEEK_CUR:
1.53 + npos = stream->pos;
1.54 + break;
1.55 + case SEEK_END:
1.56 + npos = strlen(stream->space);
1.57 + break;
1.58 + }
1.59 +
1.60 + npos += offset;
1.61 +
1.62 + if (npos < 0 || npos > stream->length) {
1.63 + return -1;
1.64 + } else {
1.65 + stream->pos = npos;
1.66 + return 0;
1.67 + }
1.68 +
1.69 +}
1.70 +
1.71 +int ucx_memeof(UcxMemstream *stream) {
1.72 + return stream->pos >= stream->length;
1.73 +}
1.74 +
1.75 +int ucx_memoverflow(UcxMemstream *stream) {
1.76 + return stream->pos > stream->length;
1.77 +}
1.78 +
1.79 +size_t ucx_memtell(UcxMemstream *stream) {
1.80 + return stream->pos;
1.81 +}
1.82 +
1.83 +size_t ucx_memio(void* d, size_t s, size_t n, UcxMemstream *m, _Bool read) {
1.84 + size_t len;
1.85 + if (m->pos + s*n > m->length) {
1.86 + if (ucx_memoverflow(m)) {
1.87 + len = 0;
1.88 + } else {
1.89 + len = m->length - m->pos;
1.90 + if (s > 1) len -= len%s;
1.91 + }
1.92 + } else {
1.93 + len = s*n;
1.94 + }
1.95 +
1.96 + if (len == 0) {
1.97 + return 0;
1.98 + }
1.99 +
1.100 + if (read) {
1.101 + memcpy(d, m->space+m->pos, len);
1.102 + } else {
1.103 + memcpy(m->space+m->pos, d, len);
1.104 + }
1.105 + m->pos += len;
1.106 +
1.107 + return len;
1.108 +}
1.109 +
1.110 +int ucx_memputc(UcxMemstream *stream, int c) {
1.111 + if (ucx_memeof(stream)) {
1.112 + return EOF;
1.113 + } else {
1.114 + c &= 0xFF;
1.115 + ((char*)(stream->space))[stream->pos] = (char) c;
1.116 + stream->pos++;
1.117 + return c;
1.118 + }
1.119 +}
1.120 +
1.121 +int ucx_memgetc(UcxMemstream *stream) {
1.122 + if (ucx_memeof(stream)) {
1.123 + return EOF;
1.124 + } else {
1.125 + int c = ((char*)(stream->space))[stream->pos];
1.126 + stream->pos++;
1.127 + return c;
1.128 + }
1.129 +}
1.130 +
1.131 +int ucx_memprintf(UcxMemstream *stream, const char* format, ...) {
1.132 + va_list v;
1.133 + va_start(v, format);
1.134 + int r = vsprintf(stream->space+stream->pos, format, v);
1.135 + va_end(v);
1.136 +
1.137 + stream->pos += r;
1.138 +
1.139 + return r;
1.140 +}
1.141 +
1.142 +int ucx_memscanf(UcxMemstream *stream, const char* format, ...) {
1.143 +
1.144 + /* TODO: vsscanf returns the number of fields read,
1.145 + * we need the number of bytes */
1.146 +
1.147 + va_list v;
1.148 + va_start(v, format);
1.149 + int r = vsscanf(stream->space+stream->pos, format, v);
1.150 + va_end(v);
1.151 +
1.152 + stream->pos += r;
1.153 +
1.154 + return r;
1.155 +}
