diff options
Diffstat (limited to 'buffer.c')
| -rw-r--r-- | buffer.c | 179 |
1 files changed, 92 insertions, 87 deletions
@@ -1,20 +1,20 @@ /* - -buffer.c - -Author: Tatu Ylonen <ylo@cs.hut.fi> - -Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland - All rights reserved - -Created: Sat Mar 18 04:15:33 1995 ylo - -Functions for manipulating fifo buffers (that can grow if needed). - -*/ + * + * buffer.c + * + * Author: Tatu Ylonen <ylo@cs.hut.fi> + * + * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland + * All rights reserved + * + * Created: Sat Mar 18 04:15:33 1995 ylo + * + * Functions for manipulating fifo buffers (that can grow if needed). + * + */ #include "includes.h" -RCSID("$Id: buffer.c,v 1.1 1999/10/27 03:42:43 damien Exp $"); +RCSID("$Id: buffer.c,v 1.2 1999/11/24 13:26:22 damien Exp $"); #include "xmalloc.h" #include "buffer.h" @@ -22,129 +22,134 @@ RCSID("$Id: buffer.c,v 1.1 1999/10/27 03:42:43 damien Exp $"); /* Initializes the buffer structure. */ -void buffer_init(Buffer *buffer) +void +buffer_init(Buffer *buffer) { - buffer->alloc = 4096; - buffer->buf = xmalloc(buffer->alloc); - buffer->offset = 0; - buffer->end = 0; + buffer->alloc = 4096; + buffer->buf = xmalloc(buffer->alloc); + buffer->offset = 0; + buffer->end = 0; } /* Frees any memory used for the buffer. */ -void buffer_free(Buffer *buffer) +void +buffer_free(Buffer *buffer) { - memset(buffer->buf, 0, buffer->alloc); - xfree(buffer->buf); + memset(buffer->buf, 0, buffer->alloc); + xfree(buffer->buf); } /* Clears any data from the buffer, making it empty. This does not actually zero the memory. */ -void buffer_clear(Buffer *buffer) +void +buffer_clear(Buffer *buffer) { - buffer->offset = 0; - buffer->end = 0; + buffer->offset = 0; + buffer->end = 0; } /* Appends data to the buffer, expanding it if necessary. */ -void buffer_append(Buffer *buffer, const char *data, unsigned int len) +void +buffer_append(Buffer *buffer, const char *data, unsigned int len) { - char *cp; - buffer_append_space(buffer, &cp, len); - memcpy(cp, data, len); + char *cp; + buffer_append_space(buffer, &cp, len); + memcpy(cp, data, len); } /* Appends space to the buffer, expanding the buffer if necessary. This does not actually copy the data into the buffer, but instead returns a pointer to the allocated region. */ -void buffer_append_space(Buffer *buffer, char **datap, unsigned int len) +void +buffer_append_space(Buffer *buffer, char **datap, unsigned int len) { - /* If the buffer is empty, start using it from the beginning. */ - if (buffer->offset == buffer->end) - { - buffer->offset = 0; - buffer->end = 0; - } - - restart: - /* If there is enough space to store all data, store it now. */ - if (buffer->end + len < buffer->alloc) - { - *datap = buffer->buf + buffer->end; - buffer->end += len; - return; - } - - /* If the buffer is quite empty, but all data is at the end, move the - data to the beginning and retry. */ - if (buffer->offset > buffer->alloc / 2) - { - memmove(buffer->buf, buffer->buf + buffer->offset, - buffer->end - buffer->offset); - buffer->end -= buffer->offset; - buffer->offset = 0; - goto restart; - } - - /* Increase the size of the buffer and retry. */ - buffer->alloc += len + 32768; - buffer->buf = xrealloc(buffer->buf, buffer->alloc); - goto restart; + /* If the buffer is empty, start using it from the beginning. */ + if (buffer->offset == buffer->end) { + buffer->offset = 0; + buffer->end = 0; + } +restart: + /* If there is enough space to store all data, store it now. */ + if (buffer->end + len < buffer->alloc) { + *datap = buffer->buf + buffer->end; + buffer->end += len; + return; + } + /* If the buffer is quite empty, but all data is at the end, move + the data to the beginning and retry. */ + if (buffer->offset > buffer->alloc / 2) { + memmove(buffer->buf, buffer->buf + buffer->offset, + buffer->end - buffer->offset); + buffer->end -= buffer->offset; + buffer->offset = 0; + goto restart; + } + /* Increase the size of the buffer and retry. */ + buffer->alloc += len + 32768; + buffer->buf = xrealloc(buffer->buf, buffer->alloc); + goto restart; } /* Returns the number of bytes of data in the buffer. */ -unsigned int buffer_len(Buffer *buffer) +unsigned int +buffer_len(Buffer *buffer) { - return buffer->end - buffer->offset; + return buffer->end - buffer->offset; } /* Gets data from the beginning of the buffer. */ -void buffer_get(Buffer *buffer, char *buf, unsigned int len) +void +buffer_get(Buffer *buffer, char *buf, unsigned int len) { - if (len > buffer->end - buffer->offset) - fatal("buffer_get trying to get more bytes than in buffer"); - memcpy(buf, buffer->buf + buffer->offset, len); - buffer->offset += len; + if (len > buffer->end - buffer->offset) + fatal("buffer_get trying to get more bytes than in buffer"); + memcpy(buf, buffer->buf + buffer->offset, len); + buffer->offset += len; } /* Consumes the given number of bytes from the beginning of the buffer. */ -void buffer_consume(Buffer *buffer, unsigned int bytes) +void +buffer_consume(Buffer *buffer, unsigned int bytes) { - if (bytes > buffer->end - buffer->offset) - fatal("buffer_get trying to get more bytes than in buffer"); - buffer->offset += bytes; -} + if (bytes > buffer->end - buffer->offset) + fatal("buffer_get trying to get more bytes than in buffer"); + buffer->offset += bytes; +} /* Consumes the given number of bytes from the end of the buffer. */ -void buffer_consume_end(Buffer *buffer, unsigned int bytes) +void +buffer_consume_end(Buffer *buffer, unsigned int bytes) { - if (bytes > buffer->end - buffer->offset) - fatal("buffer_get trying to get more bytes than in buffer"); - buffer->end -= bytes; -} + if (bytes > buffer->end - buffer->offset) + fatal("buffer_get trying to get more bytes than in buffer"); + buffer->end -= bytes; +} /* Returns a pointer to the first used byte in the buffer. */ -char *buffer_ptr(Buffer *buffer) +char * +buffer_ptr(Buffer *buffer) { - return buffer->buf + buffer->offset; + return buffer->buf + buffer->offset; } /* Dumps the contents of the buffer to stderr. */ -void buffer_dump(Buffer *buffer) +void +buffer_dump(Buffer *buffer) { - int i; - unsigned char *ucp = (unsigned char *)buffer->buf; - - for (i = buffer->offset; i < buffer->end; i++) - fprintf(stderr, " %02x", ucp[i]); - fprintf(stderr, "\n"); + int i; + unsigned char *ucp = (unsigned char *) buffer->buf; + + for (i = buffer->offset; i < buffer->end; i++) + fprintf(stderr, " %02x", ucp[i]); + fprintf(stderr, "\n"); } |