bfstd: Rename from util and reorganize it

20 files changed, 419 insertions, 402 deletions

diff --git a/Makefile b/Makefile
index a251234..66126df 100644
--- a/Makefile
+++ b/Makefile
@@ -203,6 +203,7 @@ all: $(BIN)/bfs $(BIN)/tests/mksock $(BIN)/tests/trie $(BIN)/tests/xtimegm
 
 $(BIN)/bfs: \
     $(OBJ)/src/bar.o \
+    $(OBJ)/src/bfstd.o \
     $(OBJ)/src/bftw.o \
     $(OBJ)/src/color.o \
     $(OBJ)/src/ctx.o \
@@ -222,7 +223,6 @@ $(BIN)/bfs: \
     $(OBJ)/src/stat.o \
     $(OBJ)/src/trie.o \
     $(OBJ)/src/typo.o \
-    $(OBJ)/src/util.o \
     $(OBJ)/src/xregex.o \
     $(OBJ)/src/xspawn.o \
     $(OBJ)/src/xtime.o
diff --git a/src/bar.c b/src/bar.c
index b0e595e..c656b14 100644
--- a/src/bar.c
+++ b/src/bar.c
@@ -15,8 +15,8 @@
  ****************************************************************************/
 
 #include "bar.h"
+#include "bfstd.h"
 #include "dstring.h"
-#include "util.h"
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
diff --git a/src/util.c b/src/bfstd.c
index da54040..043e8e5 100644
--- a/src/util.c
+++ b/src/bfstd.c
@@ -14,7 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           *
  ****************************************************************************/
 
-#include "util.h"
+#include "bfstd.h"
 #include "config.h"
 #include "dstring.h"
 #include "xregex.h"
@@ -42,75 +42,197 @@
 #	include <util.h>
 #endif
 
-char *xreadlinkat(int fd, const char *path, size_t size) {
-	ssize_t len;
-	char *name = NULL;
+bool is_nonexistence_error(int error) {
+	return error == ENOENT || errno == ENOTDIR;
+}
 
-	if (size == 0) {
-		size = 64;
+const char *xbasename(const char *path) {
+	const char *i;
+
+	// Skip trailing slashes
+	for (i = path + strlen(path); i > path && i[-1] == '/'; --i);
+
+	// Find the beginning of the name
+	for (; i > path && i[-1] != '/'; --i);
+
+	// Skip leading slashes
+	for (; i[0] == '/' && i[1]; ++i);
+
+	return i;
+}
+
+void close_quietly(int fd) {
+	int error = errno;
+	xclose(fd);
+	errno = error;
+}
+
+int xclose(int fd) {
+	int ret = close(fd);
+	if (ret != 0) {
+		assert(errno != EBADF);
+	}
+	return ret;
+}
+
+FILE *xfopen(const char *path, int flags) {
+	char mode[4];
+
+	switch (flags & O_ACCMODE) {
+	case O_RDONLY:
+		strcpy(mode, "rb");
+		break;
+	case O_WRONLY:
+		strcpy(mode, "wb");
+		break;
+	case O_RDWR:
+		strcpy(mode, "r+b");
+		break;
+	default:
+		assert(!"Invalid access mode");
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (flags & O_APPEND) {
+		mode[0] = 'a';
+	}
+
+	int fd;
+	if (flags & O_CREAT) {
+		fd = open(path, flags, 0666);
 	} else {
-		++size; // NUL terminator
+		fd = open(path, flags);
 	}
 
-	while (true) {
-		char *new_name = realloc(name, size);
-		if (!new_name) {
-			goto error;
+	if (fd < 0) {
+		return NULL;
+	}
+
+	FILE *ret = fdopen(fd, mode);
+	if (!ret) {
+		close_quietly(fd);
+		return NULL;
+	}
+
+	return ret;
+}
+
+char *xgetdelim(FILE *file, char delim) {
+	char *chunk = NULL;
+	size_t n = 0;
+	ssize_t len = getdelim(&chunk, &n, delim, file);
+	if (len >= 0) {
+		if (chunk[len] == delim) {
+			chunk[len] = '\0';
 		}
-		name = new_name;
+		return chunk;
+	} else {
+		free(chunk);
+		if (!ferror(file)) {
+			errno = 0;
+		}
+		return NULL;
+	}
+}
 
-		len = readlinkat(fd, path, name, size);
-		if (len < 0) {
-			goto error;
-		} else if ((size_t)len >= size) {
-			size *= 2;
-		} else {
+size_t xread(int fd, void *buf, size_t nbytes) {
+	size_t count = 0;
+
+	while (count < nbytes) {
+		ssize_t ret = read(fd, (char *)buf + count, nbytes - count);
+		if (ret < 0) {
+			if (errno == EINTR) {
+				continue;
+			} else {
+				break;
+			}
+		} else if (ret == 0) {
+			// EOF
+			errno = 0;
 			break;
+		} else {
+			count += ret;
 		}
 	}
 
-	name[len] = '\0';
-	return name;
+	return count;
+}
 
-error:
-	free(name);
-	return NULL;
+size_t xwrite(int fd, const void *buf, size_t nbytes) {
+	size_t count = 0;
+
+	while (count < nbytes) {
+		ssize_t ret = write(fd, (const char *)buf + count, nbytes - count);
+		if (ret < 0) {
+			if (errno == EINTR) {
+				continue;
+			} else {
+				break;
+			}
+		} else if (ret == 0) {
+			// EOF?
+			errno = 0;
+			break;
+		} else {
+			count += ret;
+		}
+	}
+
+	return count;
 }
 
-int dup_cloexec(int fd) {
-#ifdef F_DUPFD_CLOEXEC
-	return fcntl(fd, F_DUPFD_CLOEXEC, 0);
-#else
-	int ret = dup(fd);
-	if (ret < 0) {
+/** Compile and execute a regular expression for xrpmatch(). */
+static int xrpregex(nl_item item, const char *response) {
+	const char *pattern = nl_langinfo(item);
+	if (!pattern) {
 		return -1;
 	}
 
-	if (fcntl(ret, F_SETFD, FD_CLOEXEC) == -1) {
-		close_quietly(ret);
-		return -1;
+	struct bfs_regex *regex;
+	int ret = bfs_regcomp(&regex, pattern, BFS_REGEX_POSIX_EXTENDED, 0);
+	if (ret == 0) {
+		ret = bfs_regexec(regex, response, 0);
 	}
 
+	bfs_regfree(regex);
 	return ret;
-#endif
 }
 
-int pipe_cloexec(int pipefd[2]) {
-#if __linux__ || (BSD && !__APPLE__)
-	return pipe2(pipefd, O_CLOEXEC);
-#else
-	if (pipe(pipefd) != 0) {
+/** Check if a response is affirmative or negative. */
+static int xrpmatch(const char *response) {
+	int ret = xrpregex(NOEXPR, response);
+	if (ret > 0) {
+		return 0;
+	} else if (ret < 0) {
 		return -1;
 	}
 
-	if (fcntl(pipefd[0], F_SETFD, FD_CLOEXEC) == -1 || fcntl(pipefd[1], F_SETFD, FD_CLOEXEC) == -1) {
-		close_quietly(pipefd[1]);
-		close_quietly(pipefd[0]);
+	ret = xrpregex(YESEXPR, response);
+	if (ret > 0) {
+		return 1;
+	} else if (ret < 0) {
 		return -1;
 	}
 
-	return 0;
-#endif
+	// Failsafe: always handle y/n
+	char c = response[0];
+	if (c == 'n' || c == 'N') {
+		return 0;
+	} else if (c == 'y' || c == 'Y') {
+		return 1;
+	} else {
+		return -1;
+	}
+}
+
+int ynprompt(void) {
+	fflush(stderr);
+
+	char *line = xgetdelim(stdin, '\n');
+	int ret = line ? xrpmatch(line) : -1;
+	free(line);
+	return ret;
 }
 
 /** Get the single character describing the given file type. */
@@ -195,19 +317,88 @@ void xstrmode(mode_t mode, char str[11]) {
 	}
 }
 
-const char *xbasename(const char *path) {
-	const char *i;
+dev_t xmakedev(int ma, int mi) {
+#ifdef makedev
+	return makedev(ma, mi);
+#else
+	return (ma << 8) | mi;
+#endif
+}
 
-	// Skip trailing slashes
-	for (i = path + strlen(path); i > path && i[-1] == '/'; --i);
+int xmajor(dev_t dev) {
+#ifdef major
+	return major(dev);
+#else
+	return dev >> 8;
+#endif
+}
 
-	// Find the beginning of the name
-	for (; i > path && i[-1] != '/'; --i);
+int xminor(dev_t dev) {
+#ifdef minor
+	return minor(dev);
+#else
+	return dev & 0xFF;
+#endif
+}
 
-	// Skip leading slashes
-	for (; i[0] == '/' && i[1]; ++i);
+int dup_cloexec(int fd) {
+#ifdef F_DUPFD_CLOEXEC
+	return fcntl(fd, F_DUPFD_CLOEXEC, 0);
+#else
+	int ret = dup(fd);
+	if (ret < 0) {
+		return -1;
+	}
 
-	return i;
+	if (fcntl(ret, F_SETFD, FD_CLOEXEC) == -1) {
+		close_quietly(ret);
+		return -1;
+	}
+
+	return ret;
+#endif
+}
+
+int pipe_cloexec(int pipefd[2]) {
+#if __linux__ || (BSD && !__APPLE__)
+	return pipe2(pipefd, O_CLOEXEC);
+#else
+	if (pipe(pipefd) != 0) {
+		return -1;
+	}
+
+	if (fcntl(pipefd[0], F_SETFD, FD_CLOEXEC) == -1 || fcntl(pipefd[1], F_SETFD, FD_CLOEXEC) == -1) {
+		close_quietly(pipefd[1]);
+		close_quietly(pipefd[0]);
+		return -1;
+	}
+
+	return 0;
+#endif
+}
+
+char *xconfstr(int name) {
+#if __ANDROID__
+	errno = ENOTSUP;
+	return NULL;
+#else
+	size_t len = confstr(name, NULL, 0);
+	if (len == 0) {
+		return NULL;
+	}
+
+	char *str = malloc(len);
+	if (!str) {
+		return NULL;
+	}
+
+	if (confstr(name, str, len) != len) {
+		free(str);
+		return NULL;
+	}
+
+	return str;
+#endif // !__ANDROID__
 }
 
 int xfaccessat(int fd, const char *path, int amode) {
@@ -224,6 +415,41 @@ int xfaccessat(int fd, const char *path, int amode) {
 	return ret;
 }
 
+char *xreadlinkat(int fd, const char *path, size_t size) {
+	ssize_t len;
+	char *name = NULL;
+
+	if (size == 0) {
+		size = 64;
+	} else {
+		++size; // NUL terminator
+	}
+
+	while (true) {
+		char *new_name = realloc(name, size);
+		if (!new_name) {
+			goto error;
+		}
+		name = new_name;
+
+		len = readlinkat(fd, path, name, size);
+		if (len < 0) {
+			goto error;
+		} else if ((size_t)len >= size) {
+			size *= 2;
+		} else {
+			break;
+		}
+	}
+
+	name[len] = '\0';
+	return name;
+
+error:
+	free(name);
+	return NULL;
+}
+
 int xstrtofflags(const char **str, unsigned long long *set, unsigned long long *clear) {
 #if BSD && !__GNU__
 	char *str_arg = (char *)*str;
@@ -284,229 +510,3 @@ size_t xstrwidth(const char *str) {
 
 	return ret;
 }
-
-bool is_nonexistence_error(int error) {
-	return error == ENOENT || errno == ENOTDIR;
-}
-
-/** Compile and execute a regular expression for xrpmatch(). */
-static int xrpregex(nl_item item, const char *response) {
-	const char *pattern = nl_langinfo(item);
-	if (!pattern) {
-		return -1;
-	}
-
-	struct bfs_regex *regex;
-	int ret = bfs_regcomp(&regex, pattern, BFS_REGEX_POSIX_EXTENDED, 0);
-	if (ret == 0) {
-		ret = bfs_regexec(regex, response, 0);
-	}
-
-	bfs_regfree(regex);
-	return ret;
-}
-
-/** Check if a response is affirmative or negative. */
-static int xrpmatch(const char *response) {
-	int ret = xrpregex(NOEXPR, response);
-	if (ret > 0) {
-		return 0;
-	} else if (ret < 0) {
-		return -1;
-	}
-
-	ret = xrpregex(YESEXPR, response);
-	if (ret > 0) {
-		return 1;
-	} else if (ret < 0) {
-		return -1;
-	}
-
-	// Failsafe: always handle y/n
-	char c = response[0];
-	if (c == 'n' || c == 'N') {
-		return 0;
-	} else if (c == 'y' || c == 'Y') {
-		return 1;
-	} else {
-		return -1;
-	}
-}
-
-int ynprompt(void) {
-	fflush(stderr);
-
-	char *line = xgetdelim(stdin, '\n');
-	int ret = line ? xrpmatch(line) : -1;
-	free(line);
-	return ret;
-}
-
-dev_t bfs_makedev(int ma, int mi) {
-#ifdef makedev
-	return makedev(ma, mi);
-#else
-	return (ma << 8) | mi;
-#endif
-}
-
-int bfs_major(dev_t dev) {
-#ifdef major
-	return major(dev);
-#else
-	return dev >> 8;
-#endif
-}
-
-int bfs_minor(dev_t dev) {
-#ifdef minor
-	return minor(dev);
-#else
-	return dev & 0xFF;
-#endif
-}
-
-size_t xread(int fd, void *buf, size_t nbytes) {
-	size_t count = 0;
-
-	while (count < nbytes) {
-		ssize_t ret = read(fd, (char *)buf + count, nbytes - count);
-		if (ret < 0) {
-			if (errno == EINTR) {
-				continue;
-			} else {
-				break;
-			}
-		} else if (ret == 0) {
-			// EOF
-			errno = 0;
-			break;
-		} else {
-			count += ret;
-		}
-	}
-
-	return count;
-}
-
-size_t xwrite(int fd, const void *buf, size_t nbytes) {
-	size_t count = 0;
-
-	while (count < nbytes) {
-		ssize_t ret = write(fd, (const char *)buf + count, nbytes - count);
-		if (ret < 0) {
-			if (errno == EINTR) {
-				continue;
-			} else {
-				break;
-			}
-		} else if (ret == 0) {
-			// EOF?
-			errno = 0;
-			break;
-		} else {
-			count += ret;
-		}
-	}
-
-	return count;
-}
-
-char *xconfstr(int name) {
-#if __ANDROID__
-	errno = ENOTSUP;
-	return NULL;
-#else
-	size_t len = confstr(name, NULL, 0);
-	if (len == 0) {
-		return NULL;
-	}
-
-	char *str = malloc(len);
-	if (!str) {
-		return NULL;
-	}
-
-	if (confstr(name, str, len) != len) {
-		free(str);
-		return NULL;
-	}
-
-	return str;
-#endif // !__ANDROID__
-}
-
-char *xgetdelim(FILE *file, char delim) {
-	char *chunk = NULL;
-	size_t n = 0;
-	ssize_t len = getdelim(&chunk, &n, delim, file);
-	if (len >= 0) {
-		if (chunk[len] == delim) {
-			chunk[len] = '\0';
-		}
-		return chunk;
-	} else {
-		free(chunk);
-		if (!ferror(file)) {
-			errno = 0;
-		}
-		return NULL;
-	}
-}
-
-FILE *xfopen(const char *path, int flags) {
-	char mode[4];
-
-	switch (flags & O_ACCMODE) {
-	case O_RDONLY:
-		strcpy(mode, "rb");
-		break;
-	case O_WRONLY:
-		strcpy(mode, "wb");
-		break;
-	case O_RDWR:
-		strcpy(mode, "r+b");
-		break;
-	default:
-		assert(!"Invalid access mode");
-		errno = EINVAL;
-		return NULL;
-	}
-
-	if (flags & O_APPEND) {
-		mode[0] = 'a';
-	}
-
-	int fd;
-	if (flags & O_CREAT) {
-		fd = open(path, flags, 0666);
-	} else {
-		fd = open(path, flags);
-	}
-
-	if (fd < 0) {
-		return NULL;
-	}
-
-	FILE *ret = fdopen(fd, mode);
-	if (!ret) {
-		close_quietly(fd);
-		return NULL;
-	}
-
-	return ret;
-}
-
-int xclose(int fd) {
-	int ret = close(fd);
-	if (ret != 0) {
-		assert(errno != EBADF);
-	}
-	return ret;
-}
-
-void close_quietly(int fd) {
-	int error = errno;
-	xclose(fd);
-	errno = error;
-}
diff --git a/src/util.h b/src/bfstd.h
index 2d99152..3ad2116 100644
--- a/src/util.h
+++ b/src/bfstd.h
@@ -15,113 +15,107 @@
  ****************************************************************************/
 
 /**
- * Assorted utilities that don't belong anywhere else.
+ * Standard library wrappers and polyfills.
  */
 
-#ifndef BFS_UTIL_H
-#define BFS_UTIL_H
+#ifndef BFS_BFSTD_H
+#define BFS_BFSTD_H
 
-#include <fcntl.h>
-#include <fnmatch.h>
 #include <stdbool.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <sys/types.h>
 
-// Some portability concerns
+// #include <errno.h>
 
-#if !defined(FNM_CASEFOLD) && defined(FNM_IGNORECASE)
-#	define FNM_CASEFOLD FNM_IGNORECASE
-#endif
+/**
+ * Return whether an error code is due to a path not existing.
+ */
+bool is_nonexistence_error(int error);
+
+#include <fcntl.h>
 
 #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>
+
 /**
- * readlinkat() wrapper that dynamically allocates the result.
+ * basename() variant that doesn't modify the input.
  *
- * @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.
+ *         The path in question.
+ * @return A pointer into path at the base name offset.
  */
-char *xreadlinkat(int fd, const char *path, size_t size);
+const char *xbasename(const char *path);
 
-/**
- * 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);
+#include <stdio.h>
 
 /**
- * Like pipe(), but set the FD_CLOEXEC flag.
+ * close() variant that preserves errno.
  *
- * @param pipefd
- *         The array to hold the two file descriptors.
- * @return 0 on success, -1 on failure.
+ * @param fd
+ *         The file descriptor to close.
  */
-int pipe_cloexec(int pipefd[2]);
+void close_quietly(int fd);
 
 /**
- * Format a mode like ls -l (e.g. -rw-r--r--).
+ * close() wrapper that asserts the file descriptor is valid.
  *
- * @param mode
- *         The mode to format.
- * @param str
- *         The string to hold the formatted mode.
+ * @param fd
+ *         The file descriptor to close.
+ * @return
+ *         0 on success, or -1 on error.
  */
-void xstrmode(mode_t mode, char str[11]);
+int xclose(int fd);
 
 /**
- * basename() variant that doesn't modify the input.
+ * fopen() variant that takes open() style flags.
  *
  * @param path
- *         The path in question.
- * @return A pointer into path at the base name offset.
+ *         The path to open.
+ * @param flags
+ *         Flags to pass to open().
  */
-const char *xbasename(const char *path);
+FILE *xfopen(const char *path, int flags);
 
 /**
- * Wrapper for faccessat() that handles some portability issues.
+ * 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).
  */
-int xfaccessat(int fd, const char *path, int amode);
+char *xgetdelim(FILE *file, char delim);
 
 /**
- * Portability wrapper for strtofflags().
+ * A safe version of read() that handles interrupted system calls and partial
+ * reads.
  *
- * @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.
+ *         The number of bytes read.  A value != nbytes indicates an error
+ *         (errno != 0) or end of file (errno == 0).
  */
-int xstrtofflags(const char **str, unsigned long long *set, unsigned long long *clear);
+size_t xread(int fd, void *buf, size_t nbytes);
 
 /**
- * wcswidth() variant that works on narrow strings.
+ * A safe version of write() that handles interrupted system calls and partial
+ * writes.
  *
- * @param str
- *         The string to measure.
  * @return
- *         The likely width of that string in a terminal.
+           The number of bytes written.  A value != nbytes indicates an error.
  */
-size_t xstrwidth(const char *str);
+size_t xwrite(int fd, const void *buf, size_t nbytes);
 
-/**
- * Return whether an error code is due to a path not existing.
- */
-bool is_nonexistence_error(int error);
+// #include <stdlib.h>
 
 /**
  * Process a yes/no prompt.
@@ -130,39 +124,56 @@ bool is_nonexistence_error(int error);
  */
 int ynprompt(void);
 
+// #include <string.h>
+
+/**
+ * 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/types.h>
+
 /**
  * Portable version of makedev().
  */
-dev_t bfs_makedev(int ma, int mi);
+dev_t xmakedev(int ma, int mi);
 
 /**
  * Portable version of major().
  */
-int bfs_major(dev_t dev);
+int xmajor(dev_t dev);
 
 /**
  * Portable version of minor().
  */
-int bfs_minor(dev_t dev);
+int xminor(dev_t dev);
+
+#include <unistd.h>
 
 /**
- * A safe version of read() that handles interrupted system calls and partial
- * reads.
+ * Like dup(), but set the FD_CLOEXEC flag.
  *
+ * @param fd
+ *         The file descriptor to duplicate.
  * @return
- *         The number of bytes read.  A value != nbytes indicates an error
- *         (errno != 0) or end of file (errno == 0).
+ *         A duplicated file descriptor, or -1 on failure.
  */
-size_t xread(int fd, void *buf, size_t nbytes);
+int dup_cloexec(int fd);
 
 /**
- * A safe version of write() that handles interrupted system calls and partial
- * writes.
+ * Like pipe(), but set the FD_CLOEXEC flag.
  *
+ * @param pipefd
+ *         The array to hold the two file descriptors.
  * @return
-           The number of bytes written.  A value != nbytes indicates an error.
+ *         0 on success, -1 on failure.
  */
-size_t xwrite(int fd, const void *buf, size_t nbytes);
+int pipe_cloexec(int pipefd[2]);
 
 /**
  * Wrapper for confstr() that allocates with malloc().
@@ -175,44 +186,49 @@ size_t xwrite(int fd, const void *buf, size_t nbytes);
 char *xconfstr(int name);
 
 /**
- * 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).
+ * Wrapper for faccessat() that handles some portability issues.
  */
-char *xgetdelim(FILE *file, char delim);
+int xfaccessat(int fd, const char *path, int amode);
 
 /**
- * fopen() variant that takes open() style flags.
+ * readlinkat() wrapper that dynamically allocates the result.
  *
+ * @param fd
+ *         The base directory descriptor.
  * @param path
- *         The path to open.
- * @param flags
- *         Flags to pass to open().
+ *         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.
  */
-FILE *xfopen(const char *path, int flags);
+char *xreadlinkat(int fd, const char *path, size_t size);
 
 /**
- * close() wrapper that asserts the file descriptor is valid.
+ * Portability wrapper for strtofflags().
  *
- * @param fd
- *         The file descriptor to close.
+ * @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, or -1 on error.
+ *         0 on success, -1 on failure.
  */
-int xclose(int fd);
+int xstrtofflags(const char **str, unsigned long long *set, unsigned long long *clear);
+
+// #include <wchar.h>
 
 /**
- * close() variant that preserves errno.
+ * wcswidth() variant that works on narrow strings.
  *
- * @param fd
- *         The file descriptor to close.
+ * @param str
+ *         The string to measure.
+ * @return
+ *         The likely width of that string in a terminal.
  */
-void close_quietly(int fd);
+size_t xstrwidth(const char *str);
 
-#endif // BFS_UTIL_H
+#endif // BFS_BFSTD_H
diff --git a/src/bftw.c b/src/bftw.c
index 6f97bf6..378a225 100644
--- a/src/bftw.c
+++ b/src/bftw.c
@@ -31,13 +31,13 @@
  */
 
 #include "bftw.h"
+#include "bfstd.h"
 #include "dir.h"
 #include "darray.h"
 #include "dstring.h"
 #include "mtab.h"
 #include "stat.h"
 #include "trie.h"
-#include "util.h"
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
diff --git a/src/color.c b/src/color.c
index 6240b9c..98fe9f2 100644
--- a/src/color.c
+++ b/src/color.c
@@ -15,6 +15,7 @@
  ****************************************************************************/
 
 #include "color.h"
+#include "bfstd.h"
 #include "bftw.h"
 #include "dir.h"
 #include "dstring.h"
@@ -22,7 +23,6 @@
 #include "fsade.h"
 #include "stat.h"
 #include "trie.h"
-#include "util.h"
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
diff --git a/src/diag.c b/src/diag.c
index 27848f1..a9be5b4 100644
--- a/src/diag.c
+++ b/src/diag.c
@@ -15,10 +15,10 @@
  ****************************************************************************/
 
 #include "diag.h"
+#include "bfstd.h"
 #include "ctx.h"
 #include "color.h"
 #include "expr.h"
-#include "util.h"
 #include <assert.h>
 #include <errno.h>
 #include <stdarg.h>
diff --git a/src/diag.h b/src/diag.h
index 39129cc..56ad39b 100644
--- a/src/diag.h
+++ b/src/diag.h
@@ -22,7 +22,7 @@
 #define BFS_DIAG_H
 
 #include "ctx.h"
-#include "util.h"
+#include "config.h"
 #include <stdarg.h>
 #include <stdbool.h>
 
diff --git a/src/dir.c b/src/dir.c
index 1cd2d2c..2081cc5 100644
--- a/src/dir.c
+++ b/src/dir.c
@@ -15,8 +15,8 @@
  ****************************************************************************/
 
 #include "dir.h"
+#include "bfstd.h"
 #include "config.h"
-#include "util.h"
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
diff --git a/src/eval.c b/src/eval.c
index dc79188..5bf3120 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -20,6 +20,7 @@
 
 #include "eval.h"
 #include "bar.h"
+#include "bfstd.h"
 #include "bftw.h"
 #include "color.h"
 #include "config.h"
@@ -36,7 +37,6 @@
 #include "pwcache.h"
 #include "stat.h"
 #include "trie.h"
-#include "util.h"
 #include "xregex.h"
 #include "xtime.h"
 #include <assert.h>
@@ -686,8 +686,8 @@ bool eval_fls(const struct bfs_expr *expr, struct bfs_eval *state) {
 	}
 
 	if (ftwbuf->type == BFS_BLK || ftwbuf->type == BFS_CHR) {
-		int ma = bfs_major(statbuf->rdev);
-		int mi = bfs_minor(statbuf->rdev);
+		int ma = xmajor(statbuf->rdev);
+		int mi = xminor(statbuf->rdev);
 		if (fprintf(file, " %3d, %3d", ma, mi) < 0) {
 			goto error;
 		}
diff --git a/src/exec.c b/src/exec.c
index 0130317..afbdcb7 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -15,12 +15,12 @@
  ****************************************************************************/
 
 #include "exec.h"
+#include "bfstd.h"
 #include "bftw.h"
 #include "ctx.h"
 #include "color.h"
 #include "diag.h"
 #include "dstring.h"
-#include "util.h"
 #include "xspawn.h"
 #include <assert.h>
 #include <errno.h>
diff --git a/src/fsade.c b/src/fsade.c
index 7a7201e..a609b97 100644
--- a/src/fsade.c
+++ b/src/fsade.c
@@ -15,10 +15,11 @@
  ****************************************************************************/
 
 #include "fsade.h"
+#include "config.h"
+#include "bfstd.h"
 #include "bftw.h"
 #include "dir.h"
 #include "dstring.h"
-#include "util.h"
 #include <errno.h>
 #include <fcntl.h>
 #include <stddef.h>
diff --git a/src/main.c b/src/main.c
index 6f82976..fbddbe5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -34,6 +34,7 @@
  *
  * - Utilities:
  *     - bar.[ch]      (a terminal status bar)
+ *     - bfstd.[ch]    (standard library wrappers/polyfills)
  *     - color.[ch]    (for pretty terminal colors)
  *     - config.h      (configuration and feature/platform detection)
  *     - darray.[ch]   (a dynamic array library)
@@ -49,13 +50,12 @@
  *     - xregex.[ch]   (regular expression support)
  *     - xspawn.[ch]   (spawns processes)
  *     - xtime.[ch]    (date/time handling utilities)
- *     - util.[ch]     (everything else)
  */
 
+#include "bfstd.h"
 #include "ctx.h"
 #include "eval.h"
 #include "parse.h"
-#include "util.h"
 #include <errno.h>
 #include <fcntl.h>
 #include <locale.h>
diff --git a/src/mtab.c b/src/mtab.c
index e6a92e1..316ec6e 100644
--- a/src/mtab.c
+++ b/src/mtab.c
@@ -15,11 +15,11 @@
  ****************************************************************************/
 
 #include "mtab.h"
+#include "bfstd.h"
 #include "config.h"
 #include "darray.h"
 #include "stat.h"
 #include "trie.h"
-#include "util.h"
 #include <errno.h>
 #include <fcntl.h>
 #include <stdbool.h>
diff --git a/src/opt.c b/src/opt.c
index f8c0ba3..80fdd43 100644
--- a/src/opt.c
+++ b/src/opt.c
@@ -46,7 +46,6 @@
 #include "eval.h"
 #include "expr.h"
 #include "pwcache.h"
-#include "util.h"
 #include <assert.h>
 #include <limits.h>
 #include <stdarg.h>
diff --git a/src/parse.c b/src/parse.c
index 2fe3473..1be7cb7 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -22,6 +22,7 @@
  */
 
 #include "parse.h"
+#include "bfstd.h"
 #include "bftw.h"
 #include "color.h"
 #include "config.h"
@@ -38,7 +39,6 @@
 #include "pwcache.h"
 #include "stat.h"
 #include "typo.h"
-#include "util.h"
 #include "xregex.h"
 #include "xspawn.h"
 #include "xtime.h"
diff --git a/src/printf.c b/src/printf.c
index 8fdde41..97c203f 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -15,6 +15,7 @@
  ****************************************************************************/
 
 #include "printf.h"
+#include "bfstd.h"
 #include "bftw.h"
 #include "color.h"
 #include "ctx.h"
@@ -26,7 +27,6 @@
 #include "mtab.h"
 #include "pwcache.h"
 #include "stat.h"
-#include "util.h"
 #include "xtime.h"
 #include <assert.h>
 #include <errno.h>
diff --git a/src/stat.c b/src/stat.c
index 3134b6a..b59e9b0 100644
--- a/src/stat.c
+++ b/src/stat.c
@@ -15,8 +15,8 @@
  ****************************************************************************/
 
 #include "stat.h"
+#include "bfstd.h"
 #include "config.h"
-#include "util.h"
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -186,7 +186,7 @@ static int bfs_statx_impl(int at_fd, const char *at_path, int at_flags, struct b
 
 	buf->mask = 0;
 
-	buf->dev = bfs_makedev(xbuf.stx_dev_major, xbuf.stx_dev_minor);
+	buf->dev = xmakedev(xbuf.stx_dev_major, xbuf.stx_dev_minor);
 	buf->mask |= BFS_STAT_DEV;
 
 	if (xbuf.stx_mask & STATX_INO) {
@@ -227,7 +227,7 @@ static int bfs_statx_impl(int at_fd, const char *at_path, int at_flags, struct b
 		buf->mask |= BFS_STAT_BLOCKS;
 	}
 
-	buf->rdev = bfs_makedev(xbuf.stx_rdev_major, xbuf.stx_rdev_minor);
+	buf->rdev = xmakedev(xbuf.stx_rdev_major, xbuf.stx_rdev_minor);
 	buf->mask |= BFS_STAT_RDEV;
 
 	buf->attrs = xbuf.stx_attributes;
diff --git a/src/xregex.c b/src/xregex.c
index 4fa098d..e8d6b23 100644
--- a/src/xregex.c
+++ b/src/xregex.c
@@ -15,7 +15,8 @@
  ****************************************************************************/
 
 #include "xregex.h"
-#include "util.h"
+#include "bfstd.h"
+#include "config.h"
 #include <assert.h>
 #include <errno.h>
 #include <stdlib.h>
diff --git a/src/xspawn.c b/src/xspawn.c
index f9d52b0..5d2c320 100644
--- a/src/xspawn.c
+++ b/src/xspawn.c
@@ -15,8 +15,8 @@
  ****************************************************************************/
 
 #include "xspawn.h"
+#include "bfstd.h"
 #include "config.h"
-#include "util.h"
 #include <errno.h>
 #include <fcntl.h>
 #include <stdlib.h>