diff options
Diffstat (limited to 'girepository/cmph/buffer_entry.c')
-rw-r--r-- | girepository/cmph/buffer_entry.c | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/girepository/cmph/buffer_entry.c b/girepository/cmph/buffer_entry.c new file mode 100644 index 00000000..7f82aae1 --- /dev/null +++ b/girepository/cmph/buffer_entry.c @@ -0,0 +1,103 @@ +#include "buffer_entry.h" +#include <stdio.h> +#include <assert.h> +#include <stdlib.h> +#include <string.h> + +struct __buffer_entry_t +{ + FILE *fd; + cmph_uint8 * buff; + cmph_uint32 capacity, // buffer entry capacity + nbytes, // buffer entry used bytes + pos; // current read position in buffer entry + cmph_uint8 eof; // flag to indicate end of file +}; + +buffer_entry_t * buffer_entry_new(cmph_uint32 capacity) +{ + buffer_entry_t *buff_entry = (buffer_entry_t *)malloc(sizeof(buffer_entry_t)); + assert(buff_entry); + buff_entry->fd = NULL; + buff_entry->buff = NULL; + buff_entry->capacity = capacity; + buff_entry->nbytes = capacity; + buff_entry->pos = capacity; + buff_entry->eof = 0; + return buff_entry; +} + +void buffer_entry_open(buffer_entry_t * buffer_entry, char * filename) +{ + buffer_entry->fd = fopen(filename, "rb"); +} + +void buffer_entry_set_capacity(buffer_entry_t * buffer_entry, cmph_uint32 capacity) +{ + buffer_entry->capacity = capacity; +} + + +cmph_uint32 buffer_entry_get_capacity(buffer_entry_t * buffer_entry) +{ + return buffer_entry->capacity; +} + +void buffer_entry_load(buffer_entry_t * buffer_entry) +{ + free(buffer_entry->buff); + buffer_entry->buff = (cmph_uint8 *)calloc((size_t)buffer_entry->capacity, sizeof(cmph_uint8)); + buffer_entry->nbytes = (cmph_uint32)fread(buffer_entry->buff, (size_t)1, (size_t)buffer_entry->capacity, buffer_entry->fd); + if (buffer_entry->nbytes != buffer_entry->capacity) buffer_entry->eof = 1; + buffer_entry->pos = 0; +} + +cmph_uint8 * buffer_entry_read_key(buffer_entry_t * buffer_entry, cmph_uint32 * keylen) +{ + cmph_uint8 * buf = NULL; + cmph_uint32 lacked_bytes = sizeof(*keylen); + cmph_uint32 copied_bytes = 0; + if(buffer_entry->eof && (buffer_entry->pos == buffer_entry->nbytes)) // end + { + free(buf); + return NULL; + } + if((buffer_entry->pos + lacked_bytes) > buffer_entry->nbytes) + { + copied_bytes = buffer_entry->nbytes - buffer_entry->pos; + lacked_bytes = (buffer_entry->pos + lacked_bytes) - buffer_entry->nbytes; + if (copied_bytes != 0) memcpy(keylen, buffer_entry->buff + buffer_entry->pos, (size_t)copied_bytes); + buffer_entry_load(buffer_entry); + } + memcpy(keylen + copied_bytes, buffer_entry->buff + buffer_entry->pos, (size_t)lacked_bytes); + buffer_entry->pos += lacked_bytes; + + lacked_bytes = *keylen; + copied_bytes = 0; + buf = (cmph_uint8 *)malloc(*keylen + sizeof(*keylen)); + memcpy(buf, keylen, sizeof(*keylen)); + if((buffer_entry->pos + lacked_bytes) > buffer_entry->nbytes) { + copied_bytes = buffer_entry->nbytes - buffer_entry->pos; + lacked_bytes = (buffer_entry->pos + lacked_bytes) - buffer_entry->nbytes; + if (copied_bytes != 0) { + memcpy(buf + sizeof(*keylen), buffer_entry->buff + buffer_entry->pos, (size_t)copied_bytes); + } + buffer_entry_load(buffer_entry); + } + memcpy(buf+sizeof(*keylen)+copied_bytes, buffer_entry->buff + buffer_entry->pos, (size_t)lacked_bytes); + buffer_entry->pos += lacked_bytes; + return buf; +} + +void buffer_entry_destroy(buffer_entry_t * buffer_entry) +{ + fclose(buffer_entry->fd); + buffer_entry->fd = NULL; + free(buffer_entry->buff); + buffer_entry->buff = NULL; + buffer_entry->capacity = 0; + buffer_entry->nbytes = 0; + buffer_entry->pos = 0; + buffer_entry->eof = 0; + free(buffer_entry); +} |