1 files changed, 217 insertions, 0 deletions
diff --git a/src/diag.h b/src/diag.h
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+++ b/src/diag.h
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+// Copyright © Tavian Barnes <tavianator@tavianator.com>
+// SPDX-License-Identifier: 0BSD
+
+/**
+ * Diagnostic messages.
+ */
+
+#ifndef BFS_DIAG_H
+#define BFS_DIAG_H
+
+#include "prelude.h"
+#include <stdarg.h>
+
+/**
+ * static_assert() with an optional second argument.
+ */
+#if __STDC_VERSION__ >= C23
+#  define bfs_static_assert static_assert
+#else
+#  define bfs_static_assert(...) bfs_static_assert_(__VA_ARGS__, #__VA_ARGS__, )
+#  define bfs_static_assert_(expr, msg, ...) _Static_assert(expr, msg)
+#endif
+
+/**
+ * A source code location.
+ */
+struct bfs_loc {
+	const char *file;
+	int line;
+	const char *func;
+};
+
+#define BFS_LOC_INIT { .file = __FILE__, .line = __LINE__, .func = __func__ }
+
+/**
+ * Get the current source code location.
+ */
+#if __STDC_VERSION__ >= C23
+#  define bfs_location() (&(static const struct bfs_loc)BFS_LOC_INIT)
+#else
+#  define bfs_location() (&(const struct bfs_loc)BFS_LOC_INIT)
+#endif
+
+/**
+ * Print a low-level diagnostic message to standard error, formatted like
+ *
+ *     bfs: func@src/file.c:0: Message
+ */
+attr(printf(2, 3))
+void bfs_diagf(const struct bfs_loc *loc, const char *format, ...);
+
+/**
+ * Unconditional diagnostic message.
+ */
+#define bfs_diag(...) bfs_diagf(bfs_location(), __VA_ARGS__)
+
+/**
+ * Print a message to standard error and abort.
+ */
+attr(cold, printf(2, 3))
+noreturn void bfs_abortf(const struct bfs_loc *loc, const char *format, ...);
+
+/**
+ * Unconditional abort with a message.
+ */
+#define bfs_abort(...) bfs_abortf(bfs_location(), __VA_ARGS__)
+
+/**
+ * Abort in debug builds; no-op in release builds.
+ */
+#ifdef NDEBUG
+#  define bfs_bug(...) ((void)0)
+#else
+#  define bfs_bug bfs_abort
+#endif
+
+/**
+ * Unconditional assert.
+ */
+#define bfs_verify(...) \
+	bfs_verify_(#__VA_ARGS__, __VA_ARGS__, "", "")
+
+#define bfs_verify_(str, cond, format, ...) \
+	((cond) ? (void)0 : bfs_abort( \
+		sizeof(format) > 1 \
+			? "%.0s" format "%s%s" \
+			: "Assertion failed: `%s`%s", \
+		str, __VA_ARGS__))
+
+/**
+ * Assert in debug builds; no-op in release builds.
+ */
+#ifdef NDEBUG
+#  define bfs_assert(...) ((void)0)
+#else
+#  define bfs_assert bfs_verify
+#endif
+
+struct bfs_ctx;
+struct bfs_expr;
+
+/**
+ * Various debugging flags.
+ */
+enum debug_flags {
+	/** Print cost estimates. */
+	DEBUG_COST   = 1 << 0,
+	/** Print executed command details. */
+	DEBUG_EXEC   = 1 << 1,
+	/** Print optimization details. */
+	DEBUG_OPT    = 1 << 2,
+	/** Print rate information. */
+	DEBUG_RATES  = 1 << 3,
+	/** Trace the filesystem traversal. */
+	DEBUG_SEARCH = 1 << 4,
+	/** Trace all stat() calls. */
+	DEBUG_STAT   = 1 << 5,
+	/** Print the parse tree. */
+	DEBUG_TREE   = 1 << 6,
+	/** All debug flags. */
+	DEBUG_ALL    = (1 << 7) - 1,
+};
+
+/**
+ * Convert a debug flag to a string.
+ */
+const char *debug_flag_name(enum debug_flags flag);
+
+/**
+ * Like perror(), but decorated like bfs_error().
+ */
+attr(cold)
+void bfs_perror(const struct bfs_ctx *ctx, const char *str);
+
+/**
+ * Shorthand for printing error messages.
+ */
+attr(cold, printf(2, 3))
+void bfs_error(const struct bfs_ctx *ctx, const char *format, ...);
+
+/**
+ * Shorthand for printing warning messages.
+ *
+ * @return Whether a warning was printed.
+ */
+attr(cold, printf(2, 3))
+bool bfs_warning(const struct bfs_ctx *ctx, const char *format, ...);
+
+/**
+ * Shorthand for printing debug messages.
+ *
+ * @return Whether a debug message was printed.
+ */
+attr(cold, printf(3, 4))
+bool bfs_debug(const struct bfs_ctx *ctx, enum debug_flags flag, const char *format, ...);
+
+/**
+ * bfs_error() variant that takes a va_list.
+ */
+attr(cold, printf(2, 0))
+void bfs_verror(const struct bfs_ctx *ctx, const char *format, va_list args);
+
+/**
+ * bfs_warning() variant that takes a va_list.
+ */
+attr(cold, printf(2, 0))
+bool bfs_vwarning(const struct bfs_ctx *ctx, const char *format, va_list args);
+
+/**
+ * bfs_debug() variant that takes a va_list.
+ */
+attr(cold, printf(3, 0))
+bool bfs_vdebug(const struct bfs_ctx *ctx, enum debug_flags flag, const char *format, va_list args);
+
+/**
+ * Print the error message prefix.
+ */
+attr(cold)
+void bfs_error_prefix(const struct bfs_ctx *ctx);
+
+/**
+ * Print the warning message prefix.
+ */
+attr(cold)
+bool bfs_warning_prefix(const struct bfs_ctx *ctx);
+
+/**
+ * Print the debug message prefix.
+ */
+attr(cold)
+bool bfs_debug_prefix(const struct bfs_ctx *ctx, enum debug_flags flag);
+
+/**
+ * Highlight parts of the command line in an error message.
+ */
+attr(cold)
+void bfs_argv_error(const struct bfs_ctx *ctx, const bool args[]);
+
+/**
+ * Highlight parts of an expression in an error message.
+ */
+attr(cold)
+void bfs_expr_error(const struct bfs_ctx *ctx, const struct bfs_expr *expr);
+
+/**
+ * Highlight parts of the command line in a warning message.
+ */
+attr(cold)
+bool bfs_argv_warning(const struct bfs_ctx *ctx, const bool args[]);
+
+/**
+ * Highlight parts of an expression in a warning message.
+ */
+attr(cold)
+bool bfs_expr_warning(const struct bfs_ctx *ctx, const struct bfs_expr *expr);
+
+#endif // BFS_DIAG_H