diff options
author | Peter Tyser <ptyser@xes-inc.com> | 2009-11-09 15:17:50 -0600 |
---|---|---|
committer | Wolfgang Denk <wd@denx.de> | 2009-12-02 23:19:32 +0100 |
commit | 9ef78511cda39987e5fc10febf386fd19f58ecf7 (patch) | |
tree | 138195677feb52131cf7f4074739901a7be101cf /lib_generic | |
parent | 604f7ce55ad74694ef8743ad2e99933dc0265e46 (diff) |
circbuf: Move to lib_generic and conditionally compile
circbuf could be used as a generic library and is only currently
needed when CONFIG_USB_TTY is defined.
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Diffstat (limited to 'lib_generic')
-rw-r--r-- | lib_generic/Makefile | 1 | ||||
-rw-r--r-- | lib_generic/circbuf.c | 110 |
2 files changed, 111 insertions, 0 deletions
diff --git a/lib_generic/Makefile b/lib_generic/Makefile index 686601cc18..2ec261af4a 100644 --- a/lib_generic/Makefile +++ b/lib_generic/Makefile @@ -31,6 +31,7 @@ COBJS-$(CONFIG_BZIP2) += bzlib_crctable.o COBJS-$(CONFIG_BZIP2) += bzlib_decompress.o COBJS-$(CONFIG_BZIP2) += bzlib_randtable.o COBJS-$(CONFIG_BZIP2) += bzlib_huffman.o +COBJS-$(CONFIG_USB_TTY) += circbuf.o COBJS-y += crc16.o COBJS-y += crc32.o COBJS-y += ctype.o diff --git a/lib_generic/circbuf.c b/lib_generic/circbuf.c new file mode 100644 index 0000000000..2332c63717 --- /dev/null +++ b/lib_generic/circbuf.c @@ -0,0 +1,110 @@ +/* + * (C) Copyright 2003 + * Gerry Hamel, geh@ti.com, Texas Instruments + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <common.h> +#include <malloc.h> + +#include <circbuf.h> + + +int buf_init (circbuf_t * buf, unsigned int size) +{ + assert (buf != NULL); + + buf->size = 0; + buf->totalsize = size; + buf->data = (char *) malloc (sizeof (char) * size); + assert (buf->data != NULL); + + buf->top = buf->data; + buf->tail = buf->data; + buf->end = &(buf->data[size]); + + return 1; +} + +int buf_free (circbuf_t * buf) +{ + assert (buf != NULL); + assert (buf->data != NULL); + + free (buf->data); + memset (buf, 0, sizeof (circbuf_t)); + + return 1; +} + +int buf_pop (circbuf_t * buf, char *dest, unsigned int len) +{ + unsigned int i; + char *p = buf->top; + + assert (buf != NULL); + assert (dest != NULL); + + /* Cap to number of bytes in buffer */ + if (len > buf->size) + len = buf->size; + + for (i = 0; i < len; i++) { + dest[i] = *p++; + /* Bounds check. */ + if (p == buf->end) { + p = buf->data; + } + } + + /* Update 'top' pointer */ + buf->top = p; + buf->size -= len; + + return len; +} + +int buf_push (circbuf_t * buf, const char *src, unsigned int len) +{ + /* NOTE: this function allows push to overwrite old data. */ + unsigned int i; + char *p = buf->tail; + + assert (buf != NULL); + assert (src != NULL); + + for (i = 0; i < len; i++) { + *p++ = src[i]; + if (p == buf->end) { + p = buf->data; + } + /* Make sure pushing too much data just replaces old data */ + if (buf->size < buf->totalsize) { + buf->size++; + } else { + buf->top++; + if (buf->top == buf->end) { + buf->top = buf->data; + } + } + } + + /* Update 'tail' pointer */ + buf->tail = p; + + return len; +} |