| /* vi: set sw=4 ts=4: */ |
| /* |
| * Utility routines. |
| * |
| * Copyright (C) 2005, 2006 Rob Landley <rob@landley.net> |
| * Copyright (C) 2004 Erik Andersen <andersen@codepoet.org> |
| * Copyright (C) 2001 Matt Krai |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| #include "libbb.h" |
| |
| char* FAST_FUNC bb_get_chunk_from_file(FILE *file, int *end) |
| { |
| int ch; |
| unsigned idx = 0; |
| char *linebuf = NULL; |
| |
| while ((ch = getc(file)) != EOF) { |
| /* grow the line buffer as necessary */ |
| if (!(idx & 0xff)) |
| linebuf = xrealloc(linebuf, idx + 0x100); |
| linebuf[idx++] = (char) ch; |
| if (ch == '\0') |
| break; |
| if (end && ch == '\n') |
| break; |
| } |
| if (end) |
| *end = idx; |
| if (linebuf) { |
| // huh, does fgets discard prior data on error like this? |
| // I don't think so.... |
| //if (ferror(file)) { |
| // free(linebuf); |
| // return NULL; |
| //} |
| linebuf = xrealloc(linebuf, idx + 1); |
| linebuf[idx] = '\0'; |
| } |
| return linebuf; |
| } |
| |
| /* Get line, including trailing \n if any */ |
| char* FAST_FUNC xmalloc_fgets(FILE *file) |
| { |
| int i; |
| |
| return bb_get_chunk_from_file(file, &i); |
| } |
| /* Get line. Remove trailing \n */ |
| char* FAST_FUNC xmalloc_fgetline(FILE *file) |
| { |
| int i; |
| char *c = bb_get_chunk_from_file(file, &i); |
| |
| if (i && c[--i] == '\n') |
| c[i] = '\0'; |
| |
| return c; |
| } |
| |
| #if 0 |
| /* GNUism getline() should be faster (not tested) than a loop with fgetc */ |
| |
| /* Get line, including trailing \n if any */ |
| char* FAST_FUNC xmalloc_fgets(FILE *file) |
| { |
| char *res_buf = NULL; |
| size_t res_sz; |
| |
| if (getline(&res_buf, &res_sz, file) == -1) { |
| free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */ |
| res_buf = NULL; |
| } |
| //TODO: trimming to res_sz? |
| return res_buf; |
| } |
| /* Get line. Remove trailing \n */ |
| char* FAST_FUNC xmalloc_fgetline(FILE *file) |
| { |
| char *res_buf = NULL; |
| size_t res_sz; |
| |
| res_sz = getline(&res_buf, &res_sz, file); |
| |
| if ((ssize_t)res_sz != -1) { |
| if (res_buf[res_sz - 1] == '\n') |
| res_buf[--res_sz] = '\0'; |
| //TODO: trimming to res_sz? |
| } else { |
| free(res_buf); /* uclibc allocates a buffer even on EOF. WTF? */ |
| res_buf = NULL; |
| } |
| return res_buf; |
| } |
| |
| #endif |
| |
| #if 0 |
| /* Faster routines (~twice as fast). +170 bytes. Unused as of 2008-07. |
| * |
| * NB: they stop at NUL byte too. |
| * Performance is important here. Think "grep 50gigabyte_file"... |
| * Ironically, grep can't use it because of NUL issue. |
| * We sorely need C lib to provide fgets which reports size! |
| * |
| * Update: |
| * Actually, uclibc and glibc have it. man getline. It's GNUism, |
| * but very useful one (if it's as fast as this code). |
| * TODO: |
| * - currently, sed and sort use bb_get_chunk_from_file and heavily |
| * depend on its "stop on \n or \0" behavior, and STILL they fail |
| * to handle all cases with embedded NULs correctly. So: |
| * - audit sed and sort; convert them to getline FIRST. |
| * - THEN ditch bb_get_chunk_from_file, replace it with getline. |
| * - provide getline implementation for non-GNU systems. |
| */ |
| |
| static char* xmalloc_fgets_internal(FILE *file, int *sizep) |
| { |
| int len; |
| int idx = 0; |
| char *linebuf = NULL; |
| |
| while (1) { |
| char *r; |
| |
| linebuf = xrealloc(linebuf, idx + 0x100); |
| r = fgets(&linebuf[idx], 0x100, file); |
| if (!r) { |
| /* need to terminate in case this is error |
| * (EOF puts NUL itself) */ |
| linebuf[idx] = '\0'; |
| break; |
| } |
| /* stupid. fgets knows the len, it should report it somehow */ |
| len = strlen(&linebuf[idx]); |
| idx += len; |
| if (len != 0xff || linebuf[idx - 1] == '\n') |
| break; |
| } |
| *sizep = idx; |
| if (idx) { |
| /* xrealloc(linebuf, idx + 1) is up to caller */ |
| return linebuf; |
| } |
| free(linebuf); |
| return NULL; |
| } |
| |
| /* Get line, remove trailing \n */ |
| char* FAST_FUNC xmalloc_fgetline_fast(FILE *file) |
| { |
| int sz; |
| char *r = xmalloc_fgets_internal(file, &sz); |
| if (r && r[sz - 1] == '\n') |
| r[--sz] = '\0'; |
| return r; /* not xrealloc(r, sz + 1)! */ |
| } |
| |
| char* FAST_FUNC xmalloc_fgets(FILE *file) |
| { |
| int sz; |
| return xmalloc_fgets_internal(file, &sz); |
| } |
| |
| /* Get line, remove trailing \n */ |
| char* FAST_FUNC xmalloc_fgetline(FILE *file) |
| { |
| int sz; |
| char *r = xmalloc_fgets_internal(file, &sz); |
| if (!r) |
| return r; |
| if (r[sz - 1] == '\n') |
| r[--sz] = '\0'; |
| return xrealloc(r, sz + 1); |
| } |
| #endif |