/* getstr.c -- core function for GNU C library getline replacement function Copyright (C) 1993, 1996-2000 Free Software Foundation, Inc. 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. */ /* Written by Jan Brittenson, bson@gnu.ai.mit.edu. */ #if HAVE_CONFIG_H # include <config.h> #endif #include <stdio.h> #include <sys/types.h> #include <assert.h> #if STDC_HEADERS # include <stdlib.h> #else char *malloc (), *realloc (); #endif /* Always add at least this many bytes when extending the buffer. */ #define MIN_CHUNK 64 /* Read up to (and including) a delimiter DELIM1 from STREAM into *LINEPTR + OFFSET (and NUL-terminate it). If DELIM2 is non-zero, then read up and including the first occurrence of DELIM1 or DELIM2. *LINEPTR is a pointer returned from malloc (or NULL), pointing to *N characters of space. It is realloc'd as necessary. Return the number of characters read (not including the NUL terminator), or -1 on error or EOF. */ int getstr (char **lineptr, size_t *n, FILE *stream, int delim1, int delim2, size_t offset) { int nchars_avail; /* Allocated but unused chars in *LINEPTR. */ char *read_pos; /* Where we're reading into *LINEPTR. */ int ret; if (!lineptr || !n || !stream) return -1; if (!*lineptr) { *n = MIN_CHUNK; *lineptr = malloc (*n); if (!*lineptr) return -1; } nchars_avail = *n - offset; read_pos = *lineptr + offset; for (;;) { register int c = getc (stream); /* We always want at least one char left in the buffer, since we always (unless we get an error while reading the first char) NUL-terminate the line buffer. */ assert(*n - nchars_avail == read_pos - *lineptr); if (nchars_avail < 2) { if (*n > MIN_CHUNK) *n *= 2; else *n += MIN_CHUNK; nchars_avail = *n + *lineptr - read_pos; *lineptr = realloc (*lineptr, *n); if (!*lineptr) return -1; read_pos = *n - nchars_avail + *lineptr; assert(*n - nchars_avail == read_pos - *lineptr); } if (c == EOF || ferror (stream)) { /* Return partial line, if any. */ if (read_pos == *lineptr) return -1; else break; } *read_pos++ = c; nchars_avail--; if (c == delim1 || (delim2 && c == delim2)) /* Return the line. */ break; } /* Done - NUL terminate and return the number of chars read. */ *read_pos = '\0'; ret = read_pos - (*lineptr + offset); return ret; }