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/* ebuf.c - an expanding buffer */ |
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|
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/* Copyright 1993 Mark Russell, University of Kent at Canterbury |
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* |
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* You can do what you like with this source code as long as |
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* you don't try to make money out of it and you include an |
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* unaltered copy of this message (including the copyright). |
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*/ |
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|
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char ukcprog_ebuf_sccsid[] = "$Id: ebuf.c,v 1.1 2002/03/08 14:37:29 tdb Exp $ UKC"; |
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|
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#include <stdlib.h> |
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#include <string.h> |
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|
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#include "ukcprog.h" |
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|
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struct ebuf_s { |
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bool eb_errors_are_fatal; |
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char *eb_buf; |
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size_t eb_bufsize; |
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size_t eb_pos; |
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}; |
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|
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ebuf_t * |
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ebuf_create(errors_are_fatal) |
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bool errors_are_fatal; |
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{ |
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ebuf_t *eb; |
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char *buf; |
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size_t bufsize; |
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|
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bufsize = 100; |
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|
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if (errors_are_fatal) { |
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eb = (ebuf_t *)e_malloc(sizeof(ebuf_t)); |
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buf = e_malloc(bufsize); |
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} |
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else { |
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if ((eb = (ebuf_t *)malloc(sizeof(ebuf_t))) == NULL) |
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return NULL; |
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if ((buf = malloc(bufsize)) == NULL) { |
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free((char *)eb); |
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return NULL; |
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} |
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} |
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|
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eb->eb_errors_are_fatal = errors_are_fatal; |
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eb->eb_buf = buf; |
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eb->eb_bufsize = bufsize; |
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eb->eb_pos = 0; |
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|
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return eb; |
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} |
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|
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void |
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ebuf_reset(eb) |
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ebuf_t *eb; |
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{ |
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eb->eb_pos = 0; |
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} |
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|
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/* We would like this to take a pointer to a size_t, but that would |
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* break existing code (when compiling with gcc). Maybe later. |
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*/ |
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voidptr |
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ebuf_get(eb, p_len) |
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ebuf_t *eb; |
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int *p_len; |
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{ |
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if (p_len != NULL) |
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*p_len = eb->eb_pos; |
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return eb->eb_buf; |
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} |
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|
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ebuf_t * |
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ebuf_start(eb, errors_are_fatal) |
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ebuf_t *eb; |
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bool errors_are_fatal; |
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{ |
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if (eb == NULL) |
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eb = ebuf_create(errors_are_fatal); |
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else |
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ebuf_reset(eb); |
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|
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return eb; |
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} |
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|
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void |
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ebuf_free(eb) |
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ebuf_t *eb; |
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{ |
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free(eb->eb_buf); |
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free((char *)eb); |
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} |
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|
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int |
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ebuf_add(eb, buf, count) |
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ebuf_t *eb; |
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constvoidptr buf; |
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size_t count; |
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{ |
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size_t size; |
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|
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for (size = eb->eb_bufsize; eb->eb_pos + count > size; size *= 2) |
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; |
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|
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if (size != eb->eb_bufsize) { |
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if ((eb->eb_buf = realloc(eb->eb_buf, size)) == NULL) { |
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if (eb->eb_errors_are_fatal) |
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panic("realloc failed in ebuf_add"); |
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return -1; |
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} |
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eb->eb_bufsize = size; |
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} |
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|
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memcpy(eb->eb_buf + eb->eb_pos, buf, count); |
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eb->eb_pos += count; |
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|
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return 0; |
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} |
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|
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int |
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ebuf_addstr(eb, str) |
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ebuf_t *eb; |
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const char *str; |
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{ |
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return ebuf_add(eb, str, strlen(str)); |
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} |