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/* fpgetline.c - read an arbitrary length line from a stdio stream */ |
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|
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/* Copyright 1992 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_fpgetline_sccsid[] = "$Id: fpgetline.c,v 1.7 1993/10/09 15:22:28 mtr Exp $ UKC"; |
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|
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#ifndef __STDC__ |
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#include <sys/types.h> /* for size_t */ |
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#endif |
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|
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#include <stdio.h> |
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#include <stdlib.h> |
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|
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#include "ukcprog.h" |
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|
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#define SMALLBUF_SIZE ((size_t)200) |
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|
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char * |
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fpgetline(fp) |
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FILE *fp; |
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{ |
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static char *buf; |
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static size_t bufsize = 0; |
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int ch, pos; |
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|
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if (bufsize == 0) { |
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bufsize = 80; |
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buf = e_malloc(bufsize + 1); |
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} |
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|
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for (pos = 0; (ch = getc(fp)) != EOF && ch != '\n'; buf[pos++] = ch) { |
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if (pos == bufsize) { |
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bufsize *= 2; |
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buf = e_realloc(buf, bufsize + 1); |
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} |
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} |
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buf[pos] = '\0'; |
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|
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/* If we have a huge buffer from the last call and now have a |
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* short line, try to dump the excess. |
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*/ |
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if (pos <= SMALLBUF_SIZE && bufsize > 5000) { |
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char *smallbuf; |
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|
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if ((smallbuf = realloc(buf, SMALLBUF_SIZE + 1)) != NULL) { |
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buf = smallbuf; |
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bufsize = SMALLBUF_SIZE; |
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} |
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} |
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|
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return (pos == 0 && ch == EOF) ? NULL : buf; |
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} |