75 lines
2.3 KiB
C
75 lines
2.3 KiB
C
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/*********************/
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/* buffer.h */
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/* for Par 3.20 */
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/* Copyright 1993 by */
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/* Adam M. Costello */
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/*********************/
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/* This is ANSI C code. */
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/* Note: Those functions declared here which do not use errmsg */
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/* always succeed, provided that they are passed valid arguments. */
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#include <stddef.h>
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struct buffer;
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struct buffer *newbuffer(size_t itemsize);
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/* newbuffer(itemsize) returns a pointer to a new empty struct */
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/* buffer which holds items of size itemsize. Any struct buffer */
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/* *buf passed to any function declared in this header must */
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/* have been obtained from this function. itemsize must not be */
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/* 0. newbuffer() uses errmsg, and returns NULL on failure. */
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void freebuffer(struct buffer *buf);
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/* freebuffer(buf) frees the memory associated */
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/* with *buf. buf may not be used after this call. */
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void clearbuffer(struct buffer *buf);
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/* clearbuffer(buf) removes all items from */
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/* *buf, but does not free any memory. */
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void additem(struct buffer *buf, const void *item);
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/* additem(buf,item) copies *item to the end of *buf. item must point */
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/* to an object of the proper size for *buf. additem() uses errmsg. */
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int numitems(struct buffer *buf);
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/* numitems(buf) returns the number of items in *buf. */
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void *copyitems(struct buffer *buf);
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/* copyitems(buf) returns an array of objects of the proper size for */
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/* *buf, one for each item in *buf, or (void *) 0 if there are no items */
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/* in buf. The elements of the array are copied from the items in *buf, */
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/* in order. The array is allocated with malloc(), so it may be freed */
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/* with free(). copyitems() uses errmsg, and returns NULL on failure. */
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void *nextitem(struct buffer *buf);
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/* When buf was created by newbuffer, a pointer associated with buf */
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/* was initialized to point at the first slot in buf. If there is an */
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/* item in this slot, nextitem(buf) advances the pointer to the next */
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/* slot and returns the old value. If there is no item in the slot, */
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/* nextitem(buf) leaves the pointer where it is and returns NULL. */
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void rewindbuffer(struct buffer *buf);
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/* rewindbuffer(buf) resets the pointer used by */
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/* nextitem() to point at the first slot in buf. */
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