Merge branch 'main' into find2fdfind2fd

1 files changed, 334 insertions, 59 deletions

diff --git a/src/bfstd.h b/src/bfstd.h
index 6bf6ec8..f91e380 100644
--- a/src/bfstd.h
+++ b/src/bfstd.h
@@ -1,18 +1,5 @@
-/****************************************************************************
- * bfs                                                                      *
- * Copyright (C) 2016-2022 Tavian Barnes <tavianator@tavianator.com>        *
- *                                                                          *
- * Permission to use, copy, modify, and/or distribute this software for any *
- * purpose with or without fee is hereby granted.                           *
- *                                                                          *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES *
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         *
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  *
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   *
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    *
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  *
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           *
- ****************************************************************************/
+// Copyright © Tavian Barnes <tavianator@tavianator.com>
+// SPDX-License-Identifier: 0BSD
 
 /**
  * Standard library wrappers and polyfills.
@@ -21,57 +8,132 @@
 #ifndef BFS_BFSTD_H
 #define BFS_BFSTD_H
 
-#include <stdbool.h>
+#include "prelude.h"
+#include "sanity.h"
+#include <stddef.h>
+
+#include <ctype.h>
+
+/**
+ * Work around https://github.com/llvm/llvm-project/issues/65532 by forcing a
+ * function, not a macro, to be called.
+ */
+#if __FreeBSD__ && SANITIZE_MEMORY
+#  define BFS_INTERCEPT(fn) (fn)
+#else
+#  define BFS_INTERCEPT(fn) fn
+#endif
+
+/**
+ * Wrap isalpha()/isdigit()/etc.
+ */
+#define BFS_ISCTYPE(fn, c) BFS_INTERCEPT(fn)((unsigned char)(c))
+
+#define xisalnum(c) BFS_ISCTYPE(isalnum, c)
+#define xisalpha(c) BFS_ISCTYPE(isalpha, c)
+#define xisascii(c) BFS_ISCTYPE(isascii, c)
+#define xiscntrl(c) BFS_ISCTYPE(iscntrl, c)
+#define xisdigit(c) BFS_ISCTYPE(isdigit, c)
+#define xislower(c) BFS_ISCTYPE(islower, c)
+#define xisgraph(c) BFS_ISCTYPE(isgraph, c)
+#define xisprint(c) BFS_ISCTYPE(isprint, c)
+#define xispunct(c) BFS_ISCTYPE(ispunct, c)
+#define xisspace(c) BFS_ISCTYPE(isspace, c)
+#define xisupper(c) BFS_ISCTYPE(isupper, c)
+#define xisxdigit(c) BFS_ISCTYPE(isxdigit, c)
 
 // #include <errno.h>
 
 /**
- * Return whether an error code is due to a path not existing.
+ * Check if an error code is "like" another one.  For example, ENOTDIR is
+ * like ENOENT because they can both be triggered by non-existent paths.
+ *
+ * @param error
+ *         The error code to check.
+ * @param category
+ *         The category to test for.  Known categories include ENOENT and
+ *         ENAMETOOLONG.
+ * @return
+ *         Whether the error belongs to the given category.
+ */
+bool error_is_like(int error, int category);
+
+/**
+ * Equivalent to error_is_like(errno, category).
  */
-bool is_nonexistence_error(int error);
+bool errno_is_like(int category);
+
+/**
+ * Apply the "negative errno" convention.
+ *
+ * @param ret
+ *         The return value of the attempted operation.
+ * @return
+ *         ret, if non-negative, otherwise -errno.
+ */
+int try(int ret);
 
 #include <fcntl.h>
 
+#ifndef O_EXEC
+#  ifdef O_PATH
+#    define O_EXEC O_PATH
+#  else
+#    define O_EXEC O_RDONLY
+#  endif
+#endif
+
+#ifndef O_SEARCH
+#  ifdef O_PATH
+#    define O_SEARCH O_PATH
+#  else
+#    define O_SEARCH O_RDONLY
+#  endif
+#endif
+
 #ifndef O_DIRECTORY
-#	define O_DIRECTORY 0
+#  define O_DIRECTORY 0
 #endif
 
 #include <fnmatch.h>
 
 #if !defined(FNM_CASEFOLD) && defined(FNM_IGNORECASE)
-#	define FNM_CASEFOLD FNM_IGNORECASE
+#  define FNM_CASEFOLD FNM_IGNORECASE
 #endif
 
 // #include <libgen.h>
 
 /**
- * basename() variant that doesn't modify the input.
+ * Re-entrant dirname() variant that always allocates a copy.
  *
  * @param path
  *         The path in question.
- * @return A pointer into path at the base name offset.
+ * @return
+ *         The parent directory of the path.
  */
-const char *xbasename(const char *path);
-
-#include <stdio.h>
+char *xdirname(const char *path);
 
 /**
- * close() variant that preserves errno.
+ * Re-entrant basename() variant that always allocates a copy.
  *
- * @param fd
- *         The file descriptor to close.
+ * @param path
+ *         The path in question.
+ * @return
+ *         The final component of the path.
  */
-void close_quietly(int fd);
+char *xbasename(const char *path);
 
 /**
- * close() wrapper that asserts the file descriptor is valid.
+ * Find the offset of the final component of a path.
  *
- * @param fd
- *         The file descriptor to close.
+ * @param path
+ *         The path in question.
  * @return
- *         0 on success, or -1 on error.
+ *         The offset of the basename.
  */
-int xclose(int fd);
+size_t xbaseoff(const char *path);
+
+#include <stdio.h>
 
 /**
  * fopen() variant that takes open() style flags.
@@ -96,35 +158,94 @@ FILE *xfopen(const char *path, int flags);
  */
 char *xgetdelim(FILE *file, char delim);
 
+// #include <stdlib.h>
+
 /**
- * A safe version of read() that handles interrupted system calls and partial
- * reads.
+ * Wrapper for getprogname() or equivalent functionality.
  *
  * @return
- *         The number of bytes read.  A value != nbytes indicates an error
- *         (errno != 0) or end of file (errno == 0).
+ *         The basename of the currently running program.
  */
-size_t xread(int fd, void *buf, size_t nbytes);
+const char *xgetprogname(void);
 
 /**
- * A safe version of write() that handles interrupted system calls and partial
- * writes.
+ * Process a yes/no prompt.
+ *
+ * @return 1 for yes, 0 for no, and -1 for unknown.
+ */
+int ynprompt(void);
+
+// #include <string.h>
+
+/**
+ * Get the length of the pure-ASCII prefix of a string.
+ */
+size_t asciilen(const char *str);
+
+/**
+ * Get the length of the pure-ASCII prefix of a string.
+ *
+ * @param str
+ *         The string to check.
+ * @param n
+ *         The maximum prefix length.
+ */
+size_t asciinlen(const char *str, size_t n);
+
+/**
+ * Allocate a copy of a region of memory.
  *
+ * @param src
+ *         The memory region to copy.
+ * @param size
+ *         The size of the memory region.
  * @return
-           The number of bytes written.  A value != nbytes indicates an error.
+ *         A copy of the region, allocated with malloc(), or NULL on failure.
  */
-size_t xwrite(int fd, const void *buf, size_t nbytes);
+void *xmemdup(const void *src, size_t size);
 
-// #include <stdlib.h>
+/**
+ * A nice string copying function.
+ *
+ * @param dest
+ *         The NUL terminator of the destination string, or `end` if it is
+ *         already truncated.
+ * @param end
+ *         The end of the destination buffer.
+ * @param src
+ *         The string to copy from.
+ * @return
+ *         The new NUL terminator of the destination, or `end` on truncation.
+ */
+char *xstpecpy(char *dest, char *end, const char *src);
 
 /**
- * Process a yes/no prompt.
+ * A nice string copying function.
  *
- * @return 1 for yes, 0 for no, and -1 for unknown.
+ * @param dest
+ *         The NUL terminator of the destination string, or `end` if it is
+ *         already truncated.
+ * @param end
+ *         The end of the destination buffer.
+ * @param src
+ *         The string to copy from.
+ * @param n
+ *         The maximum number of characters to copy.
+ * @return
+ *         The new NUL terminator of the destination, or `end` on truncation.
  */
-int ynprompt(void);
+char *xstpencpy(char *dest, char *end, const char *src, size_t n);
 
-// #include <string.h>
+/**
+ * Thread-safe strerror().
+ *
+ * @param errnum
+ *         An error number.
+ * @return
+ *         A string describing that error, which remains valid until the next
+ *         xstrerror() call in the same thread.
+ */
+const char *xstrerror(int errnum);
 
 /**
  * Format a mode like ls -l (e.g. -rw-r--r--).
@@ -136,6 +257,13 @@ int ynprompt(void);
  */
 void xstrmode(mode_t mode, char str[11]);
 
+#include <sys/resource.h>
+
+/**
+ * Compare two rlim_t values, accounting for infinite limits.
+ */
+int rlim_cmp(rlim_t a, rlim_t b);
+
 #include <sys/types.h>
 
 /**
@@ -155,13 +283,30 @@ int xminor(dev_t dev);
 
 // #include <sys/stat.h>
 
-#if __APPLE__
-#	define st_atim st_atimespec
-#	define st_ctim st_ctimespec
-#	define st_mtim st_mtimespec
-#	define st_birthtim st_birthtimespec
+/**
+ * Get the access/change/modification time from a struct stat.
+ */
+#if BFS_HAS_ST_ACMTIM
+#  define ST_ATIM(sb) (sb).st_atim
+#  define ST_CTIM(sb) (sb).st_ctim
+#  define ST_MTIM(sb) (sb).st_mtim
+#elif BFS_HAS_ST_ACMTIMESPEC
+#  define ST_ATIM(sb) (sb).st_atimespec
+#  define ST_CTIM(sb) (sb).st_ctimespec
+#  define ST_MTIM(sb) (sb).st_mtimespec
+#else
+#  define ST_ATIM(sb) ((struct timespec) { .tv_sec = (sb).st_atime })
+#  define ST_CTIM(sb) ((struct timespec) { .tv_sec = (sb).st_ctime })
+#  define ST_MTIM(sb) ((struct timespec) { .tv_sec = (sb).st_mtime })
 #endif
 
+// #include <sys/wait.h>
+
+/**
+ * waitpid() wrapper that handles EINTR.
+ */
+pid_t xwaitpid(pid_t pid, int *status, int flags);
+
 // #include <unistd.h>
 
 /**
@@ -185,14 +330,41 @@ int dup_cloexec(int fd);
 int pipe_cloexec(int pipefd[2]);
 
 /**
- * Wrapper for confstr() that allocates with malloc().
+ * A safe version of read() that handles interrupted system calls and partial
+ * reads.
  *
- * @param name
- *         The ID of the confstr to look up.
  * @return
- *         The value of the confstr, or NULL on failure.
+ *         The number of bytes read.  A value != nbytes indicates an error
+ *         (errno != 0) or end of file (errno == 0).
  */
-char *xconfstr(int name);
+size_t xread(int fd, void *buf, size_t nbytes);
+
+/**
+ * A safe version of write() that handles interrupted system calls and partial
+ * writes.
+ *
+ * @return
+           The number of bytes written.  A value != nbytes indicates an error.
+ */
+size_t xwrite(int fd, const void *buf, size_t nbytes);
+
+/**
+ * close() variant that preserves errno.
+ *
+ * @param fd
+ *         The file descriptor to close.
+ */
+void close_quietly(int fd);
+
+/**
+ * close() wrapper that asserts the file descriptor is valid.
+ *
+ * @param fd
+ *         The file descriptor to close.
+ * @return
+ *         0 on success, or -1 on error.
+ */
+int xclose(int fd);
 
 /**
  * Wrapper for faccessat() that handles some portability issues.
@@ -214,6 +386,16 @@ int xfaccessat(int fd, const char *path, int amode);
 char *xreadlinkat(int fd, const char *path, size_t size);
 
 /**
+ * Wrapper for confstr() that allocates with malloc().
+ *
+ * @param name
+ *         The ID of the confstr to look up.
+ * @return
+ *         The value of the confstr, or NULL on failure.
+ */
+char *xconfstr(int name);
+
+/**
  * Portability wrapper for strtofflags().
  *
  * @param str
@@ -228,7 +410,24 @@ char *xreadlinkat(int fd, const char *path, size_t size);
  */
 int xstrtofflags(const char **str, unsigned long long *set, unsigned long long *clear);
 
-// #include <wchar.h>
+#include <wchar.h>
+
+/**
+ * Error-recovering mbrtowc() wrapper.
+ *
+ * @param str
+ *         The string to convert.
+ * @param i
+ *         The current index.
+ * @param len
+ *         The length of the string.
+ * @param mb
+ *         The multi-byte decoding state.
+ * @return
+ *         The wide character at index *i, or WEOF if decoding fails.  In either
+ *         case, *i will be advanced to the next multi-byte character.
+ */
+wint_t xmbrtowc(const char *str, size_t *i, size_t len, mbstate_t *mb);
 
 /**
  * wcswidth() variant that works on narrow strings.
@@ -240,4 +439,80 @@ int xstrtofflags(const char **str, unsigned long long *set, unsigned long long *
  */
 size_t xstrwidth(const char *str);
 
+/**
+ * wcwidth() wrapper that works around LLVM bug #65532.
+ */
+#define xwcwidth BFS_INTERCEPT(wcwidth)
+
+#include <wctype.h>
+
+/**
+ * Wrap iswalpha()/iswdigit()/etc.
+ */
+#define BFS_ISWCTYPE(fn, c) BFS_INTERCEPT(fn)(c)
+
+#define xiswalnum(c) BFS_ISWCTYPE(iswalnum, c)
+#define xiswalpha(c) BFS_ISWCTYPE(iswalpha, c)
+#define xiswcntrl(c) BFS_ISWCTYPE(iswcntrl, c)
+#define xiswdigit(c) BFS_ISWCTYPE(iswdigit, c)
+#define xiswlower(c) BFS_ISWCTYPE(iswlower, c)
+#define xiswgraph(c) BFS_ISWCTYPE(iswgraph, c)
+#define xiswprint(c) BFS_ISWCTYPE(iswprint, c)
+#define xiswpunct(c) BFS_ISWCTYPE(iswpunct, c)
+#define xiswspace(c) BFS_ISWCTYPE(iswspace, c)
+#define xiswupper(c) BFS_ISWCTYPE(iswupper, c)
+#define xiswxdigit(c) BFS_ISWCTYPE(iswxdigit, c)
+
+// #include <wordexp.h>
+
+/**
+ * Flags for wordesc().
+ */
+enum wesc_flags {
+	/**
+	 * Escape special characters so that the shell will treat the escaped
+	 * string as a single word.
+	 */
+	WESC_SHELL = 1 << 0,
+	/**
+	 * Escape special characters so that the escaped string is safe to print
+	 * to a TTY.
+	 */
+	WESC_TTY = 1 << 1,
+};
+
+/**
+ * Escape a string as a single shell word.
+ *
+ * @param dest
+ *         The destination string to fill.
+ * @param end
+ *         The end of the destination buffer.
+ * @param src
+ *         The string to escape.
+ * @param flags
+ *         Controls which characters to escape.
+ * @return
+ *         The new NUL terminator of the destination, or `end` on truncation.
+ */
+char *wordesc(char *dest, char *end, const char *str, enum wesc_flags flags);
+
+/**
+ * Escape a string as a single shell word.
+ *
+ * @param dest
+ *         The destination string to fill.
+ * @param end
+ *         The end of the destination buffer.
+ * @param src
+ *         The string to escape.
+ * @param n
+ *         The maximum length of the string.
+ * @param flags
+ *         Controls which characters to escape.
+ * @return
+ *         The new NUL terminator of the destination, or `end` on truncation.
+ */
+char *wordnesc(char *dest, char *end, const char *str, size_t n, enum wesc_flags flags);
+
 #endif // BFS_BFSTD_H