| /* Test of fwriting() function. |
| Copyright (C) 2007-2020 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 3 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, see <https://www.gnu.org/licenses/>. */ |
| |
| /* Written by Bruno Haible <bruno@clisp.org>, 2007. */ |
| |
| #include <config.h> |
| |
| /* None of the files accessed by this test are large, so disable the |
| fseek link warning if we are not using the gnulib fseek module. */ |
| #define _GL_NO_LARGE_FILES |
| #include "fwriting.h" |
| |
| #include <stdio.h> |
| |
| #include "macros.h" |
| |
| #define TESTFILE "t-fwriting.tmp" |
| |
| int |
| main () |
| { |
| FILE *fp; |
| |
| /* Create a file with some contents. Write-only file is always writing. */ |
| fp = fopen (TESTFILE, "w"); |
| if (fp == NULL) |
| goto skip; |
| ASSERT (fwriting (fp)); |
| if (fwrite ("foobarsh", 1, 8, fp) < 8) |
| goto skip; |
| ASSERT (fwriting (fp)); |
| if (fclose (fp)) |
| goto skip; |
| |
| /* Open it in read-only mode. Read-only file is never writing. */ |
| fp = fopen (TESTFILE, "r"); |
| if (fp == NULL) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'f') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fseek (fp, 2, SEEK_CUR)) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'b') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| fflush (fp); |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'a') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fseek (fp, 0, SEEK_END)) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fclose (fp)) |
| goto skip; |
| |
| /* Open it in read-write mode. POSIX requires a reposition (fseek, |
| fsetpos, rewind) or fflush when transitioning from write to read, |
| fwriting is only deterministic after input or output, but this |
| test case should be portable even on open, after reposition, and |
| after fflush. */ |
| /* First a scenario with only fgetc, fseek, fputc. */ |
| fp = fopen (TESTFILE, "r+"); |
| if (fp == NULL) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'f') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fseek (fp, 2, SEEK_CUR)) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'b') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| /* This fseek call is necessary when switching from reading to writing. |
| See the description of fopen(), ISO C 99 7.19.5.3.(6). */ |
| if (fseek (fp, 0, SEEK_CUR) != 0) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fputc ('x', fp) != 'x') |
| goto skip; |
| ASSERT (fwriting (fp)); |
| if (fseek (fp, 0, SEEK_END)) |
| goto skip; |
| /* freading (fp) is undefined here, because on some implementations (e.g. |
| glibc) fseek causes a buffer to be read. |
| fwriting (fp) is undefined as well. */ |
| if (fclose (fp)) |
| goto skip; |
| |
| /* Open it in read-write mode. POSIX requires a reposition (fseek, |
| fsetpos, rewind) or fflush when transitioning from write to read, |
| fwriting is only deterministic after input or output, but this |
| test case should be portable even on open, after reposition, and |
| after fflush. */ |
| /* Here a scenario that includes fflush. */ |
| fp = fopen (TESTFILE, "r+"); |
| if (fp == NULL) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'f') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fseek (fp, 2, SEEK_CUR)) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'b') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| fflush (fp); |
| ASSERT (!fwriting (fp)); |
| if (fgetc (fp) != 'x') |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| /* This fseek call is necessary when switching from reading to writing. |
| See the description of fopen(), ISO C 99 7.19.5.3.(6). */ |
| if (fseek (fp, 0, SEEK_CUR) != 0) |
| goto skip; |
| ASSERT (!fwriting (fp)); |
| if (fputc ('z', fp) != 'z') |
| goto skip; |
| ASSERT (fwriting (fp)); |
| if (fseek (fp, 0, SEEK_END)) |
| goto skip; |
| /* freading (fp) is undefined here, because on some implementations (e.g. |
| glibc) fseek causes a buffer to be read. |
| fwriting (fp) is undefined as well. */ |
| if (fclose (fp)) |
| goto skip; |
| |
| /* Open it in append mode. */ |
| fp = fopen (TESTFILE, "a"); |
| if (fp == NULL) |
| goto skip; |
| ASSERT (fwriting (fp)); |
| if (fwrite ("bla", 1, 3, fp) < 3) |
| goto skip; |
| ASSERT (fwriting (fp)); |
| if (fclose (fp)) |
| goto skip; |
| |
| return 0; |
| |
| skip: |
| fprintf (stderr, "Skipping test: file operations failed.\n"); |
| return 77; |
| } |