Make a printf()-style API for colored messages

8 files changed, 306 insertions, 322 deletions

diff --git a/Makefile b/Makefile
index e1d302f..ebd929a 100644
--- a/Makefile
+++ b/Makefile
@@ -16,7 +16,8 @@ VERSION := $(shell git describe --always)
 endif
 
 CC ?= gcc
-CFLAGS ?= -g -Wall
+WFLAGS ?= -Wall -Wmissing-declarations
+CFLAGS ?= -g $(WFLAGS)
 LDFLAGS ?=
 DEPFLAGS ?= -MD -MP -MF $(@:.o=.d)
 RM ?= rm -f
@@ -46,7 +47,7 @@ all: bfs
 bfs: bftw.o color.o dstring.o eval.o main.o parse.o printf.o typo.o util.o
 	$(CC) $(ALL_LDFLAGS) $^ -o $@
 
-release: CFLAGS := -O3 -flto -Wall -DNDEBUG
+release: CFLAGS := -O3 -flto $(WFLAGS) -DNDEBUG
 release: bfs
 
 %.o: %.c
diff --git a/bfs.h b/bfs.h
index b589def..708deaa 100644
--- a/bfs.h
+++ b/bfs.h
@@ -84,10 +84,10 @@ struct cmdline {
 
 	/** Color data. */
 	struct colors *colors;
-	/** Colors to use for stdout. */
-	const struct colors *stdout_colors;
-	/** Colors to use for stderr. */
-	const struct colors *stderr_colors;
+	/** Colored stdout. */
+	CFILE *cout;
+	/** Colored stderr. */
+	CFILE *cerr;
 
 	/** -mindepth option. */
 	int mindepth;
diff --git a/color.c b/color.c
index 129d032..b8acc32 100644
--- a/color.c
+++ b/color.c
@@ -11,6 +11,7 @@
 
 #include "color.h"
 #include "bftw.h"
+#include <errno.h>
 #include <stdarg.h>
 #include <stdbool.h>
 #include <stdio.h>
@@ -58,6 +59,69 @@ struct colors {
 	char *data;
 };
 
+struct color_name {
+	const char *name;
+	size_t offset;
+};
+
+#define COLOR_NAME(name, field) {name, offsetof(struct colors, field)}
+
+static const struct color_name color_names[] = {
+	COLOR_NAME("bd", block),
+	COLOR_NAME("ca", capable),
+	COLOR_NAME("cd", chardev),
+	COLOR_NAME("di", dir),
+	COLOR_NAME("do", door),
+	COLOR_NAME("er", error),
+	COLOR_NAME("ex", exec),
+	COLOR_NAME("fi", file),
+	COLOR_NAME("ln", link),
+	COLOR_NAME("mh", multi_hard),
+	COLOR_NAME("mi", missing),
+	COLOR_NAME("no", normal),
+	COLOR_NAME("or", orphan),
+	COLOR_NAME("ow", ow),
+	COLOR_NAME("pi", pipe),
+	COLOR_NAME("rs", reset),
+	COLOR_NAME("sg", setgid),
+	COLOR_NAME("so", socket),
+	COLOR_NAME("st", sticky),
+	COLOR_NAME("su", setuid),
+	COLOR_NAME("tw", sticky_ow),
+	COLOR_NAME("wr", warning),
+	{0},
+};
+
+static const char **look_up_color(const struct colors *colors, const char *name) {
+	if (!colors) {
+		return NULL;
+	}
+
+	for (const struct color_name *entry = color_names; entry->name; ++entry) {
+		if (strcmp(name, entry->name) == 0) {
+			return (const char **)((char *)colors + entry->offset);
+		}
+	}
+
+	return NULL;
+}
+
+static const char *get_color(const struct colors *colors, const char *name) {
+	const char **color = look_up_color(colors, name);
+	if (color) {
+		return *color;
+	} else {
+		return NULL;
+	}
+}
+
+static void set_color(struct colors *colors, const char *name, const char *value) {
+	const char **color = look_up_color(colors, name);
+	if (color) {
+		*color = value;
+	}
+}
+
 struct colors *parse_colors(const char *ls_colors) {
 	struct colors *colors = malloc(sizeof(struct colors));
 	if (!colors) {
@@ -117,100 +181,7 @@ struct colors *parse_colors(const char *ls_colors) {
 			continue;
 		}
 
-		switch (key[0]) {
-		case 'b':
-			if (strcmp(key, "bd") == 0) {
-				colors->block = value;
-			}
-			break;
-
-		case 'c':
-			if (strcmp(key, "ca") == 0) {
-				colors->capable = value;
-			} else if (strcmp(key, "cd") == 0) {
-				colors->chardev = value;
-			}
-			break;
-
-		case 'd':
-			if (strcmp(key, "di") == 0) {
-				colors->dir = value;
-			} else if (strcmp(key, "do") == 0) {
-				colors->door = value;
-			}
-			break;
-
-		case 'e':
-			if (strcmp(key, "ex") == 0) {
-				colors->exec = value;
-			}
-			break;
-
-		case 'f':
-			if (strcmp(key, "fi") == 0) {
-				colors->file = value;
-			}
-			break;
-
-		case 'l':
-			if (strcmp(key, "ln") == 0) {
-				colors->link = value;
-			}
-			break;
-
-		case 'm':
-			if (strcmp(key, "mh") == 0) {
-				colors->multi_hard = value;
-			} else if (strcmp(key, "mi") == 0) {
-				colors->missing = value;
-			}
-			break;
-
-		case 'n':
-			if (strcmp(key, "no") == 0) {
-				colors->normal = value;
-			}
-			break;
-
-		case 'o':
-			if (strcmp(key, "or") == 0) {
-				colors->orphan = value;
-			} else if (strcmp(key, "ow") == 0) {
-				colors->ow = value;
-			}
-			break;
-
-		case 'p':
-			if (strcmp(key, "pi") == 0) {
-				colors->pipe = value;
-			}
-			break;
-
-		case 'r':
-			if (strcmp(key, "rs") == 0) {
-				colors->reset = value;
-			}
-			break;
-
-		case 's':
-			if (strcmp(key, "sg") == 0) {
-				colors->setgid = value;
-			} else if (strcmp(key, "so") == 0) {
-				colors->socket = value;
-			} else if (strcmp(key, "st") == 0) {
-				colors->sticky = value;
-			} else if (strcmp(key, "su") == 0) {
-				colors->setuid = value;
-			}
-			break;
-
-		case 't':
-			if (strcmp(key, "tw") == 0) {
-				colors->sticky_ow = value;
-			}
-			break;
-
-		case '*':
+		if (key[0] == '*') {
 			ext = malloc(sizeof(struct ext_color));
 			if (ext) {
 				ext->ext = key + 1;
@@ -219,6 +190,8 @@ struct colors *parse_colors(const char *ls_colors) {
 				ext->next = colors->ext_list;
 				colors->ext_list = ext;
 			}
+		} else {
+			set_color(colors, key, value);
 		}
 	}
 
@@ -226,6 +199,38 @@ done:
 	return colors;
 }
 
+void free_colors(struct colors *colors) {
+	if (colors) {
+		struct ext_color *ext = colors->ext_list;
+		while (ext) {
+			struct ext_color *saved = ext;
+			ext = ext->next;
+			free(saved);
+		}
+
+		free(colors->data);
+		free(colors);
+	}
+}
+
+CFILE *cfdup(FILE *file, const struct colors *colors) {
+	CFILE *cfile = malloc(sizeof(*cfile));
+	if (cfile) {
+		cfile->file = file;
+		if (isatty(fileno(file))) {
+			cfile->colors = colors;
+		} else {
+			cfile->colors = NULL;
+		}
+	}
+	return cfile;
+}
+
+int cfclose(CFILE *cfile) {
+	free(cfile);
+	return 0;
+}
+
 static const char *file_color(const struct colors *colors, const char *filename, const struct BFTW *ftwbuf) {
 	const struct stat *sb = ftwbuf->statbuf;
 	if (!sb) {
@@ -331,102 +336,111 @@ static int print_esc(const char *esc, FILE *file) {
 	return 0;
 }
 
-int pretty_print(const struct colors *colors, const struct BFTW *ftwbuf) {
+static int print_path(CFILE *cfile, const struct BFTW *ftwbuf) {
+	const struct colors *colors = cfile->colors;
+	FILE *file = cfile->file;
 	const char *path = ftwbuf->path;
 
 	if (!colors) {
-		return puts(path) == EOF ? -1 : 0;
+		return fputs(path, file) == EOF ? -1 : 0;
 	}
 
 	const char *filename = path + ftwbuf->nameoff;
 
 	if (colors->dir) {
-		if (print_esc(colors->dir, stdout) != 0) {
+		if (print_esc(colors->dir, file) != 0) {
 			return -1;
 		}
 	}
-	if (fwrite(path, 1, ftwbuf->nameoff, stdout) != ftwbuf->nameoff) {
+	if (fwrite(path, 1, ftwbuf->nameoff, file) != ftwbuf->nameoff) {
 		return -1;
 	}
 	if (colors->dir) {
-		if (print_esc(colors->reset, stdout) != 0) {
+		if (print_esc(colors->reset, file) != 0) {
 			return -1;
 		}
 	}
 
 	const char *color = file_color(colors, filename, ftwbuf);
 	if (color) {
-		if (print_esc(color, stdout) != 0) {
+		if (print_esc(color, file) != 0) {
 			return -1;
 		}
 	}
-	if (fputs(filename, stdout) == EOF) {
+	if (fputs(filename, file) == EOF) {
 		return -1;
 	}
 	if (color) {
-		if (print_esc(colors->reset, stdout) != 0) {
+		if (print_esc(colors->reset, file) != 0) {
 			return -1;
 		}
 	}
-	if (fputs("\n", stdout) == EOF) {
-		return -1;
-	}
 
 	return 0;
 }
 
-static int pretty_format(const struct colors *colors, const char *color, const char *format, va_list args) {
-	if (color) {
-		if (print_esc(color, stderr) != 0) {
-			return -1;
-		}
-	}
-
-	if (vfprintf(stderr, format, args) < 0) {
-		return -1;
-	}
-
-	if (color) {
-		if (print_esc(colors->reset, stderr) != 0) {
-			return -1;
-		}
-	}
+int cfprintf(CFILE *cfile, const char *format, ...) {
+	const struct colors *colors = cfile->colors;
+	FILE *file = cfile->file;
 
-	return 0;
-}
+	int ret = -1;
 
-int pretty_warning(const struct colors *colors, const char *format, ...) {
 	va_list args;
 	va_start(args, format);
 
-	int ret = pretty_format(colors, colors ? colors->warning : NULL, format, args);
+	char name[3] = {0};
+	const char *esc;
 
-	va_end(args);
+	for (const char *i = format; *i; ++i) {
+		if (*i == '%') {
+			switch (*++i) {
+			case '%':
+				goto one_char;
 
-	return ret;
-}
+			case 'c':
+				if (fputc(va_arg(args, int), file) == EOF) {
+					goto done;
+				}
+				break;
 
-int pretty_error(const struct colors *colors, const char *format, ...) {
-	va_list args;
-	va_start(args, format);
+			case 's':
+				if (fputs(va_arg(args, const char *), file) == EOF) {
+					goto done;
+				}
+				break;
 
-	int ret = pretty_format(colors, colors ? colors->error : NULL, format, args);
+			case 'P':
+				if (print_path(cfile, va_arg(args, const struct BFTW *)) != 0) {
+					goto done;
+				}
+				break;
 
-	va_end(args);
+			case '{':
+				memcpy(name, i + 1, 2);
+				esc = get_color(colors, name);
+				if (esc && print_esc(esc, file) != 0) {
+					goto done;
+				}
+				i += 3;
+				break;
 
-	return ret;
-}
+			default:
+				errno = EINVAL;
+				goto done;
+			}
 
-void free_colors(struct colors *colors) {
-	if (colors) {
-		struct ext_color *ext = colors->ext_list;
-		while (ext) {
-			struct ext_color *saved = ext;
-			ext = ext->next;
-			free(saved);
+			continue;
 		}
 
-		free(colors->data);
-		free(colors);
+	one_char:
+		if (fputc(*i, file) == EOF) {
+			goto done;
+		}
 	}
+
+	ret = 0;
+
+done:
+	va_end(args);
+	return ret;
 }
diff --git a/color.h b/color.h
index 8ba397d..c3b3e41 100644
--- a/color.h
+++ b/color.h
@@ -13,6 +13,7 @@
 #define BFS_COLOR_H
 
 #include "bftw.h"
+#include <stdio.h>
 
 /**
  * A lookup table for colors.
@@ -29,54 +30,58 @@ struct colors;
 struct colors *parse_colors(const char *ls_colors);
 
 /**
- * Pretty-print a file path.
+ * Free a color table.
  *
  * @param colors
- *         The color table to use.
- * @param ftwbuf
- *         The bftw() data for the current path.
- * @return 0 on success, -1 on failure.
+ *         The color table to free.
  */
-int pretty_print(const struct colors *colors, const struct BFTW *ftwbuf);
+void free_colors(struct colors *colors);
 
-#if __GNUC__
-#	define BFS_PRINTF_ATTRIBUTE(f, v) __attribute__((format(printf, f, v)))
-#else
-#	define BFS_PRINTF_ATTRIBUTE(f, v)
-#endif
+/**
+ * A file/stream with associated colors.
+ */
+typedef struct CFILE {
+	/** The underlying file/stream. */
+	FILE *file;
+	/** The color table to use, if any. */
+	const struct colors *colors;
+} CFILE;
 
 /**
- * Pretty-print a warning message.
+ * Make a colored copy of an open file.
  *
+ * @param file
+ *         The underlying file.
  * @param colors
- *         The color table to use.
- * @param format
- *         The format string.
- * @param ...
- *         The format string's arguments.
- * @return 0 on success, -1 on failure.
+ *         The color table to use if file is a TTY.
+ * @return A colored wrapper around file.
  */
-int pretty_warning(const struct colors *colors, const char *format, ...) BFS_PRINTF_ATTRIBUTE(2, 3);
+CFILE *cfdup(FILE *file, const struct colors *colors);
 
 /**
- * Pretty-print an error message.
+ * Close a colored file.
  *
- * @param colors
- *         The color table to use.
- * @param format
- *         The format string.
- * @param ...
- *         The format string's arguments.
+ * @param cfile
+ *         The colored file to close.
  * @return 0 on success, -1 on failure.
  */
-int pretty_error(const struct colors *colors, const char *format, ...) BFS_PRINTF_ATTRIBUTE(2, 3);
+int cfclose(CFILE *cfile);
 
 /**
- * Free a color table.
+ * Colored, formatted output.
  *
- * @param colors
- *         The color table to free.
+ * @param cfile
+ *         The colored stream to print to.
+ * @param format
+ *         A printf()-style format string, supporting these format specifiers:
+ *
+ *         %%: A literal '%'
+ *         %c: A single character
+ *         %s: A string
+ *         %P: A colored file path, from a const struct BFTW * argument
+ *         %{cc}: Change the color to 'cc'
+ * @return 0 on success, -1 on failure.
  */
-void free_colors(struct colors *colors);
+int cfprintf(CFILE *cfile, const char *format, ...);
 
 #endif // BFS_COLOR_H
diff --git a/eval.c b/eval.c
index 512a05a..03dd41d 100644
--- a/eval.c
+++ b/eval.c
@@ -58,8 +58,7 @@ static bool eval_should_ignore(const struct eval_state *state, int error) {
  */
 static void eval_error(struct eval_state *state) {
 	if (!eval_should_ignore(state, errno)) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "'%s': %s\n", state->ftwbuf->path, strerror(errno));
+		cfprintf(state->cmdline->cerr, "%{er}'%s': %s%{rs}\n", state->ftwbuf->path, strerror(errno));
 		*state->ret = -1;
 	}
 }
@@ -735,12 +734,12 @@ done:
  * -print action.
  */
 bool eval_print(const struct expr *expr, struct eval_state *state) {
-	const struct colors *colors = state->cmdline->stdout_colors;
-	if (colors) {
+	CFILE *cout = state->cmdline->cout;
+	if (cout->colors) {
 		fill_statbuf(state);
 	}
 
-	if (pretty_print(colors, state->ftwbuf) != 0) {
+	if (cfprintf(cout, "%P\n", state->ftwbuf) < 0) {
 		eval_error(state);
 	}
 
@@ -785,8 +784,7 @@ bool eval_regex(const struct expr *expr, struct eval_state *state) {
 	} else if (err != REG_NOMATCH) {
 		char *str = xregerror(err, expr->regex);
 		if (str) {
-			pretty_error(state->cmdline->stderr_colors,
-			             "'%s': %s\n", path, str);
+			cfprintf(state->cmdline->cerr, "%{er}'%s': %s%{rs}\n", path, str);
 			free(str);
 		} else {
 			perror("xregerror()");
@@ -1006,7 +1004,7 @@ bool eval_comma(const struct expr *expr, struct eval_state *state) {
 /**
  * Debug stat() calls.
  */
-void debug_stat(const struct eval_state *state) {
+static void debug_stat(const struct eval_state *state) {
 	struct BFTW *ftwbuf = state->ftwbuf;
 
 	fprintf(stderr, "fstatat(");
@@ -1061,7 +1059,7 @@ static enum bftw_action cmdline_callback(struct BFTW *ftwbuf, void *ptr) {
 	if (ftwbuf->typeflag == BFTW_ERROR) {
 		if (!eval_should_ignore(&state, ftwbuf->error)) {
 			args->ret = -1;
-			pretty_error(cmdline->stderr_colors, "'%s': %s\n", ftwbuf->path, strerror(ftwbuf->error));
+			cfprintf(cmdline->cerr, "%{er}'%s': %s%{rs}\n", ftwbuf->path, strerror(ftwbuf->error));
 		}
 		state.action = BFTW_SKIP_SUBTREE;
 		goto done;
diff --git a/parse.c b/parse.c
index 81f2875..7bed320 100644
--- a/parse.c
+++ b/parse.c
@@ -188,6 +188,8 @@ void free_cmdline(struct cmdline *cmdline) {
 	if (cmdline) {
 		free_expr(cmdline->expr);
 
+		cfclose(cmdline->cerr);
+		cfclose(cmdline->cout);
 		free_colors(cmdline->colors);
 
 		struct root *root = cmdline->roots;
@@ -295,9 +297,7 @@ static int stat_arg(const struct parser_state *state, struct expr *expr, struct
 
 	int ret = fstatat(AT_FDCWD, expr->sdata, sb, flags);
 	if (ret != 0) {
-		pretty_error(cmdline->stderr_colors,
-		             "error: '%s': %s\n", expr->sdata, strerror(errno));
-		free_expr(expr);
+		cfprintf(cmdline->cerr, "%{er}error: '%s': %s%{rs}\n", expr->sdata, strerror(errno));
 	}
 	return ret;
 }
@@ -452,8 +452,7 @@ static const char *parse_int(const struct parser_state *state, const char *str,
 
 bad:
 	if (!(flags & IF_QUIET)) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: '%s' is not a valid integer.\n", str);
+		cfprintf(state->cmdline->cerr, "%{er}error: '%s' is not a valid integer.%{rs}\n", str);
 	}
 	return NULL;
 }
@@ -518,10 +517,10 @@ static struct expr *parse_option(struct parser_state *state, size_t argc) {
 	const char *arg = *parser_advance(state, T_OPTION, argc);
 
 	if (state->warn && state->non_option_seen) {
-		pretty_warning(state->cmdline->stderr_colors,
-		               "warning: The '%s' option applies to the entire command line.  For clarity, place\n"
-		               "it before any non-option arguments.\n\n",
-		               arg);
+		cfprintf(state->cmdline->cerr,
+		         "%{wr}warning: The '%s' option applies to the entire command line.  For clarity, place\n"
+		         "it before any non-option arguments.%{rs}\n\n",
+		         arg);
 	}
 
 
@@ -564,8 +563,7 @@ static struct expr *parse_unary_positional_option(struct parser_state *state, co
 	const char *arg = state->argv[0];
 	*value = state->argv[1];
 	if (!*value) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s needs a value.\n", arg);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s needs a value.%{rs}\n", arg);
 		return NULL;
 	}
 
@@ -594,8 +592,7 @@ static struct expr *parse_unary_test(struct parser_state *state, eval_fn *eval)
 	const char *arg = state->argv[0];
 	const char *value = state->argv[1];
 	if (!value) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s needs a value.\n", arg);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s needs a value.%{rs}\n", arg);
 		return NULL;
 	}
 
@@ -632,8 +629,7 @@ static struct expr *parse_unary_action(struct parser_state *state, eval_fn *eval
 	const char *arg = state->argv[0];
 	const char *value = state->argv[1];
 	if (!value) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s needs a value.\n", arg);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s needs a value.%{rs}\n", arg);
 		return NULL;
 	}
 
@@ -670,8 +666,7 @@ static struct expr *parse_debug(struct parser_state *state, int arg1, int arg2)
 	const char *arg = state->argv[0];
 	const char *flag = state->argv[1];
 	if (!flag) {
-		pretty_error(cmdline->stderr_colors,
-		             "error: %s needs a flag.\n", arg);
+		cfprintf(cmdline->cerr, "%{er}error: %s needs a flag.%{rs}\n", arg);
 		return NULL;
 	}
 
@@ -695,8 +690,7 @@ static struct expr *parse_debug(struct parser_state *state, int arg1, int arg2)
 	} else if (strcmp(flag, "tree") == 0) {
 		cmdline->debug |= DEBUG_TREE;
 	} else {
-		pretty_warning(cmdline->stderr_colors,
-		               "warning: Unrecognized debug flag '%s'.\n\n", flag);
+		cfprintf(cmdline->cerr, "%{wr}warning: Unrecognized debug flag '%s'.%{rs}\n\n", flag);
 	}
 
 	return parse_unary_flag(state);
@@ -715,9 +709,7 @@ static struct expr *parse_optlevel(struct parser_state *state, int arg1, int arg
 	}
 
 	if (*optlevel > 4) {
-		pretty_warning(state->cmdline->stderr_colors,
-		               "warning: %s is the same as -O4.\n\n",
-		               state->argv[0]);
+		cfprintf(state->cmdline->cerr, "%{wr}warning: %s is the same as -O4.%{rs}\n\n", state->argv[0]);
 	}
 
 	return parse_nullary_flag(state);
@@ -772,6 +764,7 @@ static struct expr *parse_acnewer(struct parser_state *state, int field, int arg
 
 	struct stat sb;
 	if (stat_arg(state, expr, &sb) != 0) {
+		free_expr(expr);
 		return NULL;
 	}
 
@@ -786,12 +779,13 @@ static struct expr *parse_acnewer(struct parser_state *state, int field, int arg
  */
 static struct expr *parse_color(struct parser_state *state, int color, int arg2) {
 	struct cmdline *cmdline = state->cmdline;
+	struct colors *colors = cmdline->colors;
 	if (color) {
-		cmdline->stdout_colors = cmdline->colors;
-		cmdline->stderr_colors = cmdline->colors;
+		cmdline->cout->colors = colors;
+		cmdline->cerr->colors = colors;
 	} else {
-		cmdline->stdout_colors = NULL;
-		cmdline->stderr_colors = NULL;
+		cmdline->cout->colors = NULL;
+		cmdline->cerr->colors = NULL;
 	}
 	return parse_nullary_option(state);
 }
@@ -872,8 +866,7 @@ static struct expr *parse_depth_limit(struct parser_state *state, int is_min, in
 	const char *arg = state->argv[0];
 	const char *value = state->argv[1];
 	if (!value) {
-		pretty_error(cmdline->stderr_colors,
-		             "error: %s needs a value.\n", arg);
+		cfprintf(cmdline->cerr, "%{er}error: %s needs a value.%{rs}\n", arg);
 		return NULL;
 	}
 
@@ -908,14 +901,12 @@ static struct expr *parse_exec(struct parser_state *state, int flags, int arg2)
 	}
 
 	if (!arg) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s: Expected ';' or '+'.\n", state->argv[0]);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s: Expected ';' or '+'.%{rs}\n", state->argv[0]);
 		return NULL;
 	}
 
 	if (flags & EXEC_MULTI) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s ... {} + is not supported yet.\n", state->argv[0]);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s ... {} + is not supported yet.%{rs}\n", state->argv[0]);
 		return NULL;
 	}
 
@@ -934,8 +925,7 @@ static struct expr *parse_f(struct parser_state *state, int arg1, int arg2) {
 
 	const char *path = state->argv[0];
 	if (!path) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: -f requires a path.\n");
+		cfprintf(state->cmdline->cerr, "%{er}error: -f requires a path.%{rs}\n");
 		return NULL;
 	}
 
@@ -953,8 +943,7 @@ static struct expr *parse_f(struct parser_state *state, int arg1, int arg2) {
 static int expr_open(struct parser_state *state, struct expr *expr, const char *path) {
 	expr->file = fopen(path, "wb");
 	if (!expr->file) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: '%s': %s\n", path, strerror(errno));
+		cfprintf(state->cmdline->cerr, "%{er}error: '%s': %s%{rs}\n", path, strerror(errno));
 		free_expr(expr);
 		return -1;
 	}
@@ -997,15 +986,13 @@ static struct expr *parse_fprintf(struct parser_state *state, int arg1, int arg2
 
 	const char *file = state->argv[1];
 	if (!file) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s needs a file.\n", arg);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s needs a file.%{rs}\n", arg);
 		return NULL;
 	}
 
 	const char *format = state->argv[2];
 	if (!format) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s needs a format string.\n", arg);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s needs a format string.%{rs}\n", arg);
 		return NULL;
 	}
 
@@ -1018,7 +1005,7 @@ static struct expr *parse_fprintf(struct parser_state *state, int arg1, int arg2
 		return NULL;
 	}
 
-	expr->printf = parse_bfs_printf(format, state->cmdline->stderr_colors);
+	expr->printf = parse_bfs_printf(format, state->cmdline->cerr);
 	if (!expr->printf) {
 		free_expr(expr);
 		return NULL;
@@ -1047,8 +1034,7 @@ static struct expr *parse_group(struct parser_state *state, int arg1, int arg2)
 			goto fail;
 		}
 	} else {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s %s: No such group.\n", arg, expr->sdata);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s %s: No such group.%{rs}\n", arg, expr->sdata);
 		goto fail;
 	}
 
@@ -1086,8 +1072,7 @@ static struct expr *parse_user(struct parser_state *state, int arg1, int arg2) {
 			goto fail;
 		}
 	} else {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s %s: No such user.\n", arg, expr->sdata);
+		cfprintf(state->cmdline->cerr, "%{er}error: %s %s: No such user.%{rs}\n", arg, expr->sdata);
 		goto fail;
 	}
 
@@ -1144,8 +1129,7 @@ static struct expr *set_fnm_casefold(const struct parser_state *state, struct ex
 #ifdef FNM_CASEFOLD
 			expr->idata = FNM_CASEFOLD;
 #else
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s is missing platform support.\n", expr->argv[0]);
+			cfprintf(state->cmdline->cerr, "%{er}error: %s is missing platform support.%{rs}\n", expr->argv[0]);
 			free_expr(expr);
 			return NULL;
 #endif
@@ -1186,14 +1170,13 @@ static struct expr *parse_lname(struct parser_state *state, int casefold, int ar
 static struct expr *parse_newerxy(struct parser_state *state, int arg1, int arg2) {
 	const char *arg = state->argv[0];
 	if (strlen(arg) != 8) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: Expected -newerXY; found %s.\n", arg);
+		cfprintf(state->cmdline->cerr, "%{er}error: Expected -newerXY; found %s.%{rs}\n", arg);
 		return NULL;
 	}
 
 	struct expr *expr = parse_unary_test(state, eval_acnewer);
 	if (!expr) {
-		return NULL;
+		goto fail;
 	}
 
 	switch (arg[6]) {
@@ -1208,27 +1191,21 @@ static struct expr *parse_newerxy(struct parser_state *state, int arg1, int arg2
 		break;
 
 	case 'B':
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s: File birth times ('B') are not supported.\n", arg);
-		free_expr(expr);
-		return NULL;
+		cfprintf(state->cmdline->cerr, "%{er}error: %s: File birth times ('B') are not supported.%{rs}\n", arg);
+		goto fail;
 
 	default:
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s: For -newerXY, X should be 'a', 'c', 'm', or 'B'.\n", arg);
-		free_expr(expr);
-		return NULL;
+		cfprintf(state->cmdline->cerr, "%{er}error: %s: For -newerXY, X should be 'a', 'c', 'm', or 'B'.%{rs}\n", arg);
+		goto fail;
 	}
 
 	if (arg[7] == 't') {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: %s: Explicit reference times ('t') are not supported.\n", arg);
-		free_expr(expr);
-		return NULL;
+		cfprintf(state->cmdline->cerr, "%{er}error: %s: Explicit reference times ('t') are not supported.%{rs}\n", arg);
+		goto fail;
 	} else {
 		struct stat sb;
 		if (stat_arg(state, expr, &sb) != 0) {
-			return NULL;
+			goto fail;
 		}
 
 		switch (arg[7]) {
@@ -1243,20 +1220,21 @@ static struct expr *parse_newerxy(struct parser_state *state, int arg1, int arg2
 			break;
 
 		case 'B':
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s: File birth times ('B') are not supported.\n", arg);
-			free_expr(expr);
-			return NULL;
+			cfprintf(state->cmdline->cerr, "%{er}error: %s: File birth times ('B') are not supported.%{rs}\n", arg);
+			goto fail;
 
 		default:
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s: For -newerXY, Y should be 'a', 'c', 'm', 'B', or 't'.\n", arg);
-			free_expr(expr);
-			return NULL;
+			cfprintf(state->cmdline->cerr,
+			         "%{er}error: %s: For -newerXY, Y should be 'a', 'c', 'm', 'B', or 't'.%{rs}\n", arg);
+			goto fail;
 		}
 	}
 
 	return expr;
+
+fail:
+	free_expr(expr);
+	return NULL;
 }
 
 /**
@@ -1278,9 +1256,9 @@ static struct expr *parse_nohidden(struct parser_state *state, int arg1, int arg
  */
 static struct expr *parse_noleaf(struct parser_state *state, int arg1, int arg2) {
 	if (state->warn) {
-		pretty_warning(state->cmdline->stderr_colors,
-		               "warning: bfs does not apply the optimization that %s inhibits.\n\n",
-		               state->argv[0]);
+		cfprintf(state->cmdline->cerr,
+		         "%{wr}warning: bfs does not apply the optimization that %s inhibits.%{rs}\n\n",
+		         state->argv[0]);
 	}
 
 	return parse_nullary_option(state);
@@ -1497,9 +1475,7 @@ done:
 	return 0;
 
 fail:
-	pretty_error(state->cmdline->stderr_colors,
-	             "error: '%s' is an invalid mode.\n\n",
-	             mode);
+	cfprintf(state->cmdline->cerr, "%{er}error: '%s' is an invalid mode.%{rs}\n", mode);
 	return -1;
 }
 
@@ -1567,7 +1543,7 @@ static struct expr *parse_printf(struct parser_state *state, int arg1, int arg2)
 
 	expr->file = stdout;
 
-	expr->printf = parse_bfs_printf(expr->sdata, state->cmdline->stderr_colors);
+	expr->printf = parse_bfs_printf(expr->sdata, state->cmdline->cerr);
 	if (!expr->printf) {
 		free_expr(expr);
 		return NULL;
@@ -1609,9 +1585,7 @@ static struct expr *parse_regex(struct parser_state *state, int flags, int arg2)
 	if (err != 0) {
 		char *str = xregerror(err, expr->regex);
 		if (str) {
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s %s: %s.\n",
-			             expr->argv[0], expr->argv[1], str);
+			cfprintf(state->cmdline->cerr, "%{er}error: %s %s: %s.%{rs}\n", expr->argv[0], expr->argv[1], str);
 			free(str);
 		} else {
 			perror("xregerror()");
@@ -1664,8 +1638,7 @@ static struct expr *parse_regextype(struct parser_state *state, int arg1, int ar
 	return expr;
 
 fail_bad_type:
-	pretty_error(state->cmdline->stderr_colors,
-	             "error: Unsupported -regextype '%s'.\n\n", type);
+	cfprintf(state->cmdline->cerr, "%{er}error: Unsupported -regextype '%s'.%{rs}\n\n", type);
 fail_list_types:
 	fputs("Supported types are:\n\n", file);
 	fputs("  posix-basic:    POSIX basic regular expressions (BRE)\n", file);
@@ -1686,6 +1659,7 @@ static struct expr *parse_samefile(struct parser_state *state, int arg1, int arg
 
 	struct stat sb;
 	if (stat_arg(state, expr, &sb) != 0) {
+		free_expr(expr);
 		return NULL;
 	}
 
@@ -1747,9 +1721,9 @@ static struct expr *parse_size(struct parser_state *state, int arg1, int arg2) {
 	return expr;
 
 bad_unit:
-	pretty_error(state->cmdline->stderr_colors,
-	             "error: %s %s: Expected a size unit (one of bcwkMGTP); found %s.\n",
-	             expr->argv[0], expr->argv[1], unit);
+	cfprintf(state->cmdline->cerr,
+	         "%{er}error: %s %s: Expected a size unit (one of bcwkMGTP); found %s.%{rs}\n",
+	         expr->argv[0], expr->argv[1], unit);
 fail:
 	free_expr(expr);
 	return NULL;
@@ -1803,15 +1777,15 @@ static struct expr *parse_type(struct parser_state *state, int x, int arg2) {
 			break;
 
 		case '\0':
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s %s: Expected a type flag.\n",
-			             expr->argv[0], expr->argv[1]);
+			cfprintf(state->cmdline->cerr,
+			         "%{er}error: %s %s: Expected a type flag.%{rs}\n",
+			         expr->argv[0], expr->argv[1]);
 			goto fail;
 
 		default:
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s %s: Unknown type flag '%c' (expected one of [bcdpflsD]).\n",
-			             expr->argv[0], expr->argv[1], *c);
+			cfprintf(state->cmdline->cerr,
+			         "%{er}error: %s %s: Unknown type flag '%c' (expected one of [bcdpflsD]).%{rs}\n",
+			         expr->argv[0], expr->argv[1], *c);
 			goto fail;
 		}
 
@@ -1822,9 +1796,9 @@ static struct expr *parse_type(struct parser_state *state, int x, int arg2) {
 			++c;
 			continue;
 		} else {
-			pretty_error(state->cmdline->stderr_colors,
-			             "error: %s %s: Types must be comma-separated.\n",
-			             expr->argv[0], expr->argv[1]);
+			cfprintf(state->cmdline->cerr,
+			         "%{er}error: %s %s: Types must be comma-separated.%{rs}\n",
+			         expr->argv[0], expr->argv[1]);
 			goto fail;
 		}
 	}
@@ -2070,13 +2044,13 @@ static struct expr *parse_literal(struct parser_state *state) {
 	}
 
 	match = table_lookup_fuzzy(arg + 1);
-	pretty_error(cmdline->stderr_colors,
-	             "error: Unknown argument '%s'; did you mean '-%s'?\n", arg, match->arg);
+	cfprintf(cmdline->cerr,
+	         "%{er}error: Unknown argument '%s'; did you mean '-%s'?%{rs}\n",
+		 arg, match->arg);
 	return NULL;
 
 unexpected:
-	pretty_error(cmdline->stderr_colors,
-	             "error: Expected a predicate; found '%s'.\n", arg);
+	cfprintf(cmdline->cerr, "%{er}error: Expected a predicate; found '%s'.%{rs}\n", arg);
 	return NULL;
 }
 
@@ -2477,8 +2451,7 @@ static struct expr *parse_whole_expr(struct parser_state *state) {
 	}
 
 	if (state->argv[0]) {
-		pretty_error(state->cmdline->stderr_colors,
-		             "error: Unexpected argument '%s'.\n", state->argv[0]);
+		cfprintf(state->cmdline->cerr, "%{er}error: Unexpected argument '%s'.%{rs}\n", state->argv[0]);
 		goto fail;
 	}
 
@@ -2539,7 +2512,7 @@ void dump_cmdline(const struct cmdline *cmdline, bool verbose) {
 		fprintf(stderr, "%s ", root->path);
 	}
 
-	if (cmdline->stdout_colors) {
+	if (cmdline->cout->colors) {
 		fputs("-color ", stderr);
 	} else {
 		fputs("-nocolor ", stderr);
@@ -2609,8 +2582,12 @@ struct cmdline *parse_cmdline(int argc, char *argv[]) {
 	cmdline->nopen_files = 0;
 
 	cmdline->colors = parse_colors(getenv("LS_COLORS"));
-	cmdline->stdout_colors = isatty(STDOUT_FILENO) ? cmdline->colors : NULL;
-	cmdline->stderr_colors = isatty(STDERR_FILENO) ? cmdline->colors : NULL;
+	cmdline->cout = cfdup(stdout, cmdline->colors);
+	cmdline->cerr = cfdup(stderr, cmdline->colors);
+	if (!cmdline->cout || !cmdline->cerr) {
+		perror("cfdup()");
+		goto fail;
+	}
 
 	struct parser_state state = {
 		.cmdline = cmdline,
diff --git a/printf.c b/printf.c
index b0f708f..b1ef710 100644
--- a/printf.c
+++ b/printf.c
@@ -496,7 +496,7 @@ static int append_literal(struct bfs_printf_directive ***tail, struct bfs_printf
 	return 0;
 }
 
-struct bfs_printf *parse_bfs_printf(const char *format, const struct colors *stderr_colors) {
+struct bfs_printf *parse_bfs_printf(const char *format, CFILE *cerr) {
 	struct bfs_printf *command = malloc(sizeof(*command));
 	if (!command) {
 		perror("malloc()");
@@ -551,15 +551,11 @@ struct bfs_printf *parse_bfs_printf(const char *format, const struct colors *std
 				goto done;
 
 			case '\0':
-				pretty_error(stderr_colors,
-				             "error: '%s': Incomplete escape sequence '\\'.\n",
-				             format);
+				cfprintf(cerr, "%{er}error: '%s': Incomplete escape sequence '\\'.%{rs}\n", format);
 				goto error;
 
 			default:
-				pretty_error(stderr_colors,
-				             "error: '%s': Unrecognized escape sequence '\\%c'.\n",
-				             format, c);
+				cfprintf(cerr, "%{er}error: '%s': Unrecognized escape sequence '\\%c'.%{rs}\n", format, c);
 				goto error;
 			}
 		} else if (c == '%') {
@@ -592,9 +588,7 @@ struct bfs_printf *parse_bfs_printf(const char *format, const struct colors *std
 				case ' ':
 				case '-':
 					if (strchr(directive->str, c)) {
-						pretty_error(stderr_colors,
-						             "error: '%s': Duplicate flag '%c'.\n",
-						             format, c);
+						cfprintf(cerr, "%{er}error: '%s': Duplicate flag '%c'.%{rs}\n", format, c);
 						goto directive_error;
 					}
 					if (dstrncat(&directive->str, &c, 1) != 0) {
@@ -774,36 +768,31 @@ struct bfs_printf *parse_bfs_printf(const char *format, const struct colors *std
 					break;
 
 				case '\0':
-					pretty_error(stderr_colors,
-					             "error: '%s': Incomplete time specifier '%s%c'.\n",
-					             format, directive->str, i[-1]);
+					cfprintf(cerr, "%{er}error: '%s': Incomplete time specifier '%s%c'.%{rs}\n",
+					         format, directive->str, i[-1]);
 					goto directive_error;
 
 				default:
-					pretty_error(stderr_colors,
-					             "error: '%s': Unrecognized time specifier '%%%c%c'.\n",
-					             format, i[-1], c);
+					cfprintf(cerr, "%{er}error: '%s': Unrecognized time specifier '%%%c%c'.%{rs}\n",
+					         format, i[-1], c);
 					goto directive_error;
 				}
 				break;
 
 			case '\0':
-				pretty_error(stderr_colors,
-				             "error: '%s': Incomplete format specifier '%s'.\n",
-				             format, directive->str);
+				cfprintf(cerr, "%{er}error: '%s': Incomplete format specifier '%s'.%{rs}\n",
+				         format, directive->str);
 				goto directive_error;
 
 			default:
-				pretty_error(stderr_colors,
-				             "error: '%s': Unrecognized format specifier '%%%c'.\n",
-				             format, c);
+				cfprintf(cerr, "%{er}error: '%s': Unrecognized format specifier '%%%c'.%{rs}\n",
+				         format, c);
 				goto directive_error;
 			}
 
 			if (must_be_numeric && strcmp(specifier, "s") == 0) {
-				pretty_error(stderr_colors,
-				             "error: '%s': Invalid flags '%s' for string format '%%%c'.\n",
-				             format, directive->str + 1, c);
+				cfprintf(cerr, "%{er}error: '%s': Invalid flags '%s' for string format '%%%c'.%{rs}\n",
+				         format, directive->str + 1, c);
 				goto directive_error;
 			}
 
diff --git a/printf.h b/printf.h
index 34eda0a..32171ca 100644
--- a/printf.h
+++ b/printf.h
@@ -34,11 +34,11 @@ struct bfs_printf {
  *
  * @param format
  *         The format string to parse.
- * @param stderr_colors
- *         Color table for printing error messages.
+ * @param cerr
+ *         For error messages.
  * @return The parsed printf command, or NULL on failure.
  */
-struct bfs_printf *parse_bfs_printf(const char *format, const struct colors *stderr_colors);
+struct bfs_printf *parse_bfs_printf(const char *format, CFILE *cerr);
 
 /**
  * Evaluate a parsed format string.