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Diffstat (limited to 'src/bfstd.h')
| -rw-r--r-- | src/bfstd.h | 518 |
1 files changed, 518 insertions, 0 deletions
diff --git a/src/bfstd.h b/src/bfstd.h new file mode 100644 index 0000000..f91e380 --- /dev/null +++ b/src/bfstd.h @@ -0,0 +1,518 @@ +// Copyright © Tavian Barnes <tavianator@tavianator.com> +// SPDX-License-Identifier: 0BSD + +/** + * Standard library wrappers and polyfills. + */ + +#ifndef BFS_BFSTD_H +#define BFS_BFSTD_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> + +/** + * 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 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 +#endif + +#include <fnmatch.h> + +#if !defined(FNM_CASEFOLD) && defined(FNM_IGNORECASE) +# define FNM_CASEFOLD FNM_IGNORECASE +#endif + +// #include <libgen.h> + +/** + * Re-entrant dirname() variant that always allocates a copy. + * + * @param path + * The path in question. + * @return + * The parent directory of the path. + */ +char *xdirname(const char *path); + +/** + * Re-entrant basename() variant that always allocates a copy. + * + * @param path + * The path in question. + * @return + * The final component of the path. + */ +char *xbasename(const char *path); + +/** + * Find the offset of the final component of a path. + * + * @param path + * The path in question. + * @return + * The offset of the basename. + */ +size_t xbaseoff(const char *path); + +#include <stdio.h> + +/** + * fopen() variant that takes open() style flags. + * + * @param path + * The path to open. + * @param flags + * Flags to pass to open(). + */ +FILE *xfopen(const char *path, int flags); + +/** + * Convenience wrapper for getdelim(). + * + * @param file + * The file to read. + * @param delim + * The delimiter character to split on. + * @return + * The read chunk (without the delimiter), allocated with malloc(). + * NULL is returned on error (errno != 0) or end of file (errno == 0). + */ +char *xgetdelim(FILE *file, char delim); + +// #include <stdlib.h> + +/** + * Wrapper for getprogname() or equivalent functionality. + * + * @return + * The basename of the currently running program. + */ +const char *xgetprogname(void); + +/** + * 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 + * A copy of the region, allocated with malloc(), or NULL on failure. + */ +void *xmemdup(const void *src, size_t size); + +/** + * 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); + +/** + * 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. + * @param n + * The maximum number of characters to copy. + * @return + * The new NUL terminator of the destination, or `end` on truncation. + */ +char *xstpencpy(char *dest, char *end, const char *src, size_t n); + +/** + * 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--). + * + * @param mode + * The mode to format. + * @param str + * The string to hold the formatted mode. + */ +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> + +/** + * Portable version of makedev(). + */ +dev_t xmakedev(int ma, int mi); + +/** + * Portable version of major(). + */ +int xmajor(dev_t dev); + +/** + * Portable version of minor(). + */ +int xminor(dev_t dev); + +// #include <sys/stat.h> + +/** + * 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> + +/** + * Like dup(), but set the FD_CLOEXEC flag. + * + * @param fd + * The file descriptor to duplicate. + * @return + * A duplicated file descriptor, or -1 on failure. + */ +int dup_cloexec(int fd); + +/** + * Like pipe(), but set the FD_CLOEXEC flag. + * + * @param pipefd + * The array to hold the two file descriptors. + * @return + * 0 on success, -1 on failure. + */ +int pipe_cloexec(int pipefd[2]); + +/** + * A safe version of read() that handles interrupted system calls and partial + * reads. + * + * @return + * The number of bytes read. A value != nbytes indicates an error + * (errno != 0) or end of file (errno == 0). + */ +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. + */ +int xfaccessat(int fd, const char *path, int amode); + +/** + * readlinkat() wrapper that dynamically allocates the result. + * + * @param fd + * The base directory descriptor. + * @param path + * The path to the link, relative to fd. + * @param size + * An estimate for the size of the link name (pass 0 if unknown). + * @return + * The target of the link, allocated with malloc(), or NULL on failure. + */ +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 + * The string to parse. The pointee will be advanced to the first + * invalid position on error. + * @param set + * The flags that are set in the string. + * @param clear + * The flags that are cleared in the string. + * @return + * 0 on success, -1 on failure. + */ +int xstrtofflags(const char **str, unsigned long long *set, unsigned long long *clear); + +#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. + * + * @param str + * The string to measure. + * @return + * The likely width of that string in a terminal. + */ +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 |