version 1.26, 2006/03/25 13:17:01 |
version 1.27, 2006/04/16 00:48:52 |
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#include "buffer.h" |
#include "buffer.h" |
#include "log.h" |
#include "log.h" |
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#define BUFFER_MAX_CHUNK 0x100000 |
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#define BUFFER_MAX_LEN 0xa00000 |
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#define BUFFER_ALLOCSZ 0x008000 |
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/* Initializes the buffer structure. */ |
/* Initializes the buffer structure. */ |
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void |
void |
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memcpy(p, data, len); |
memcpy(p, data, len); |
} |
} |
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static int |
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buffer_compact(Buffer *buffer) |
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{ |
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/* |
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* If the buffer is quite empty, but all data is at the end, move the |
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* data to the beginning. |
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*/ |
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if (buffer->offset > MIN(buffer->alloc, BUFFER_MAX_CHUNK)) { |
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memmove(buffer->buf, buffer->buf + buffer->offset, |
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buffer->end - buffer->offset); |
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buffer->end -= buffer->offset; |
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buffer->offset = 0; |
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return (1); |
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} |
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return (0); |
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} |
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/* |
/* |
* Appends space to the buffer, expanding the buffer if necessary. This does |
* 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 |
* not actually copy the data into the buffer, but instead returns a pointer |
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buffer->end += len; |
buffer->end += len; |
return p; |
return p; |
} |
} |
/* |
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* If the buffer is quite empty, but all data is at the end, move the |
/* Compact data back to the start of the buffer if necessary */ |
* data to the beginning and retry. |
if (buffer_compact(buffer)) |
*/ |
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if (buffer->offset > MIN(buffer->alloc, BUFFER_MAX_CHUNK)) { |
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memmove(buffer->buf, buffer->buf + buffer->offset, |
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buffer->end - buffer->offset); |
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buffer->end -= buffer->offset; |
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buffer->offset = 0; |
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goto restart; |
goto restart; |
} |
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/* Increase the size of the buffer and retry. */ |
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newlen = buffer->alloc + len + 32768; |
/* Increase the size of the buffer and retry. */ |
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newlen = roundup(buffer->alloc + len, BUFFER_ALLOCSZ); |
if (newlen > BUFFER_MAX_LEN) |
if (newlen > BUFFER_MAX_LEN) |
fatal("buffer_append_space: alloc %u not supported", |
fatal("buffer_append_space: alloc %u not supported", |
newlen); |
newlen); |
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buffer->alloc = newlen; |
buffer->alloc = newlen; |
goto restart; |
goto restart; |
/* NOTREACHED */ |
/* NOTREACHED */ |
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} |
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/* |
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* Check whether an allocation of 'len' will fit in the buffer |
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* This must follow the same math as buffer_append_space |
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*/ |
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int |
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buffer_check_alloc(Buffer *buffer, u_int len) |
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{ |
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if (buffer->offset == buffer->end) { |
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buffer->offset = 0; |
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buffer->end = 0; |
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} |
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restart: |
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if (buffer->end + len < buffer->alloc) |
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return (1); |
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if (buffer_compact(buffer)) |
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goto restart; |
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if (roundup(buffer->alloc + len, BUFFER_ALLOCSZ) <= BUFFER_MAX_LEN) |
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return (1); |
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return (0); |
} |
} |
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/* Returns the number of bytes of data in the buffer. */ |
/* Returns the number of bytes of data in the buffer. */ |