diff options
Diffstat (limited to 'support/readdir.h')
-rw-r--r-- | support/readdir.h | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/support/readdir.h b/support/readdir.h new file mode 100644 index 0000000000..7d7c7650d4 --- /dev/null +++ b/support/readdir.h @@ -0,0 +1,85 @@ +/* Type-generic wrapper for readdir functions. + Copyright (C) 2024 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#ifndef SUPPORT_READDIR_H +#define SUPPORT_READDIR_H + +#include <dirent.h> +#include <stdbool.h> +#include <stdint.h> + +__BEGIN_DECLS + +/* Definition independent of _FILE_OFFSET_BITS. */ +struct support_dirent +{ + uint64_t d_ino; + uint64_t d_off; /* 0 if d_off is not supported. */ + uint32_t d_type; + char *d_name; +}; + +/* Operation to be performed by support_readdir below. */ +enum support_readdir_op + { + SUPPORT_READDIR, + SUPPORT_READDIR64, + SUPPORT_READDIR_R, + SUPPORT_READDIR64_R, + SUPPORT_READDIR64_COMPAT, + SUPPORT_READDIR64_R_COMPAT, + }; + +/* Returns the last supported function. May exclude + SUPPORT_READDIR64_R_COMPAT if not implemented. */ +enum support_readdir_op support_readdir_op_last (void); + +/* Returns the name of the function that corresponds to the OP constant. */ +const char *support_readdir_function (enum support_readdir_op op); + +/* Returns the d_ino field width for OP, in bits. */ +unsigned int support_readdir_inode_width (enum support_readdir_op op); + +/* Returns the d_off field width for OP, in bits. Zero if not present. */ +unsigned int support_readdir_offset_width (enum support_readdir_op op); + +/* Returns true if OP is an _r variant with name length restrictions. */ +bool support_readdir_r_variant (enum support_readdir_op op); + +/* First, free E->d_name and set the field to NULL. Then call the + readdir variant as specified by OP. If successfully, copy fields + to E, make a copy of the entry name using strdup, and write its + addres sto E->d_name. + + Return true if an entry was read, or false if the end of the + directory stream was reached. Terminates the process upon error. + The caller is expected to free E->d_name if the function is not + called again for this E. + + Note that this function assumes that E->d_name has been initialized + to NULL or has been allocated by a previous call to this function. */ +bool support_readdir (DIR *stream, enum support_readdir_op op, + struct support_dirent *e) __nonnull ((1, 3)); + +/* Checks that the readdir operation OP fails with errno value EXPECTED. */ +void support_readdir_expect_error (DIR *stream, enum support_readdir_op op, + int expected) __nonnull ((1)); + +__END_DECLS + +#endif /* SUPPORT_READDIR_H */ |