Factor out shared backtrace code (#1793)

Makefile

@@ -73,6 +73,7 @@ rgbasm_obj := \
 	src/asm/symbol.o \
 	src/asm/warning.o \
 	src/extern/utf8decoder.o \
+	src/backtrace.o \
 	src/linkdefs.o \
 	src/opmath.o \
 	src/util.o \
@@ -96,6 +97,7 @@ rgblink_obj := \
 	src/link/symbol.o \
 	src/link/warning.o \
 	src/extern/utf8decoder.o \
+	src/backtrace.o \
 	src/linkdefs.o \
 	src/opmath.o \
 	src/util.o \

include/backtrace.hpp

@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: MIT
+
+#ifndef RGBDS_BACKTRACE_HPP
+#define RGBDS_BACKTRACE_HPP
+
+#include <inttypes.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <vector>
+
+#include "style.hpp"
+
+static constexpr uint64_t TRACE_COLLAPSE = UINT64_MAX;
+
+extern uint64_t traceDepth;
+
+bool trace_ParseTraceDepth(char const *arg);
+
+template<typename T, typename M, typename N>
+void trace_PrintBacktrace(std::vector<T> const &stack, M getName, N getLineNo) {
+	auto printLocation = [&](T const &item) {
+		style_Set(stderr, STYLE_CYAN, true);
+		fputs(getName(item), stderr);
+		style_Set(stderr, STYLE_CYAN, false);
+		fprintf(stderr, "(%" PRIu32 ")", getLineNo(item));
+	};
+
+	size_t n = stack.size();
+
+	if (traceDepth == TRACE_COLLAPSE) {
+		fputs("   ", stderr); // Just three spaces; the fourth will be handled by the loop
+		for (size_t i = 0; i < n; ++i) {
+			style_Reset(stderr);
+			fprintf(stderr, " %s ", i == 0 ? "at" : "<-");
+			printLocation(stack[n - i - 1]);
+		}
+		putc('\n', stderr);
+	} else if (traceDepth == 0 || static_cast<size_t>(traceDepth) >= n) {
+		for (size_t i = 0; i < n; ++i) {
+			style_Reset(stderr);
+			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
+			printLocation(stack[n - i - 1]);
+			putc('\n', stderr);
+		}
+	} else {
+		size_t last = traceDepth / 2;
+		size_t first = traceDepth - last;
+		size_t skipped = n - traceDepth;
+		for (size_t i = 0; i < first; ++i) {
+			style_Reset(stderr);
+			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
+			printLocation(stack[n - i - 1]);
+			putc('\n', stderr);
+		}
+		style_Reset(stderr);
+		fprintf(stderr, "    ...%zu more%s\n", skipped, last ? "..." : "");
+		for (size_t i = n - last; i < n; ++i) {
+			style_Reset(stderr);
+			fputs("    <- ", stderr);
+			printLocation(stack[n - i - 1]);
+			putc('\n', stderr);
+		}
+	}
+
+	style_Reset(stderr);
+}
+
+#endif // RGBDS_BACKTRACE_HPP

include/diagnostics.hpp

@@ -53,15 +53,12 @@ struct DiagnosticsState {
 	bool warningsAreErrors = false;
 };
 
-static constexpr uint64_t TRACE_COLLAPSE = UINT64_MAX;
-
 template<typename L, typename W>
 struct Diagnostics {
 	std::vector<WarningFlag<L>> metaWarnings;
 	std::vector<WarningFlag<L>> warningFlags;
 	std::vector<ParamWarning<W>> paramWarnings;
 	DiagnosticsState<W> state;
-	uint64_t traceDepth;
 	uint64_t nbErrors;
 
 	void incrementErrors() {

src/CMakeLists.txt

@@ -51,6 +51,7 @@ set(rgbasm_src
     "asm/symbol.cpp"
     "asm/warning.cpp"
     "extern/utf8decoder.cpp"
+    "backtrace.cpp"
     "linkdefs.cpp"
     "opmath.cpp"
     "util.cpp"
@@ -72,6 +73,7 @@ set(rgblink_src
     "link/symbol.cpp"
     "link/warning.cpp"
     "extern/utf8decoder.cpp"
+    "backtrace.cpp"
     "linkdefs.cpp"
     "opmath.cpp"
     "util.cpp"

src/asm/fstack.cpp

@@ -11,11 +11,11 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "backtrace.hpp"
 #include "diagnostics.hpp"
 #include "helpers.hpp"
 #include "linkdefs.hpp"
 #include "platform.hpp" // S_ISDIR (stat macro)
-#include "style.hpp"
 #include "verbosity.hpp"
 
 #include "asm/lexer.hpp"
@@ -78,53 +78,12 @@ std::vector<std::pair<std::string, uint32_t>> FileStackNode::backtrace(uint32_t
 	}
 }
 
-static void printNode(std::pair<std::string, uint32_t> const &node) {
-	style_Set(stderr, STYLE_CYAN, true);
-	fputs(node.first.c_str(), stderr);
-	style_Set(stderr, STYLE_CYAN, false);
-	fprintf(stderr, "(%" PRIu32 ")", node.second);
-}
-
 void FileStackNode::printBacktrace(uint32_t curLineNo) const {
-	std::vector<std::pair<std::string, uint32_t>> nodes = backtrace(curLineNo);
-	size_t n = nodes.size();
-
-	if (warnings.traceDepth == TRACE_COLLAPSE) {
-		fputs("   ", stderr); // Just three spaces; the fourth will be handled by the loop
-		for (size_t i = 0; i < n; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, " %s ", i == 0 ? "at" : "<-");
-			printNode(nodes[n - i - 1]);
-		}
-		putc('\n', stderr);
-	} else if (warnings.traceDepth == 0 || static_cast<size_t>(warnings.traceDepth) >= n) {
-		for (size_t i = 0; i < n; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
-			printNode(nodes[n - i - 1]);
-			putc('\n', stderr);
-		}
-	} else {
-		size_t last = warnings.traceDepth / 2;
-		size_t first = warnings.traceDepth - last;
-		size_t skipped = n - warnings.traceDepth;
-		for (size_t i = 0; i < first; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
-			printNode(nodes[n - i - 1]);
-			putc('\n', stderr);
-		}
-		style_Reset(stderr);
-		fprintf(stderr, "    ...%zu more%s\n", skipped, last ? "..." : "");
-		for (size_t i = n - last; i < n; ++i) {
-			style_Reset(stderr);
-			fputs("    <- ", stderr);
-			printNode(nodes[n - i - 1]);
-			putc('\n', stderr);
-		}
-	}
-
-	style_Reset(stderr);
+	trace_PrintBacktrace(
+	    backtrace(curLineNo),
+	    [](std::pair<std::string, uint32_t> const &node) { return node.first.c_str(); },
+	    [](std::pair<std::string, uint32_t> const &node) { return node.second; }
+	);
 }
 
 void fstk_TraceCurrent() {

src/asm/main.cpp

@@ -11,6 +11,7 @@
 #include <string.h>
 #include <time.h>
 
+#include "backtrace.hpp"
 #include "diagnostics.hpp"
 #include "extern/getopt.hpp"
 #include "helpers.hpp"
@@ -303,23 +304,11 @@ int main(int argc, char *argv[]) {
 		switch (ch) {
 			char *endptr;
 
-		case 'B': {
-			if (!strcasecmp(musl_optarg, "collapse")) {
-				warnings.traceDepth = TRACE_COLLAPSE;
-				break;
-			}
-
-			warnings.traceDepth = strtoul(musl_optarg, &endptr, 0);
-
-			if (musl_optarg[0] == '\0' || *endptr != '\0') {
+		case 'B':
+			if (!trace_ParseTraceDepth(musl_optarg)) {
 				fatal("Invalid argument for option '-B'");
 			}
-
-			if (warnings.traceDepth >= UINT64_MAX) {
-				fatal("Argument for option '-B' is too large");
-			}
 			break;
-		}
 
 		case 'b':
 			if (strlen(musl_optarg) == 2) {

src/asm/warning.cpp

@@ -60,7 +60,6 @@ Diagnostics<WarningLevel, WarningID> warnings = {
         {WARNING_UNMAPPED_CHAR_1,  WARNING_UNMAPPED_CHAR_2,  1},
     },
     .state = DiagnosticsState<WarningID>(),
-    .traceDepth = 0,
     .nbErrors = 0,
 };
 // clang-format on

src/backtrace.cpp

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: MIT
+
+#include "backtrace.hpp"
+
+#include <stdlib.h> // strtoul
+
+#include "platform.hpp" // strcasecmp
+
+uint64_t traceDepth = 0;
+
+bool trace_ParseTraceDepth(char const *arg) {
+	if (!strcasecmp(arg, "collapse")) {
+		traceDepth = TRACE_COLLAPSE;
+		return true;
+	}
+
+	char *endptr;
+	traceDepth = strtoul(arg, &endptr, 0);
+
+	return arg[0] != '\0' && *endptr == '\0' && traceDepth != TRACE_COLLAPSE;
+}

src/fix/warning.cpp

@@ -19,7 +19,6 @@ Diagnostics<WarningLevel, WarningID> warnings = {
     },
     .paramWarnings = {},
     .state = DiagnosticsState<WarningID>(),
-    .traceDepth = 0,
     .nbErrors = 0,
 };
 // clang-format on

src/gfx/warning.cpp

@@ -22,7 +22,6 @@ Diagnostics<WarningLevel, WarningID> warnings = {
     },
     .paramWarnings = {},
     .state = DiagnosticsState<WarningID>(),
-    .traceDepth = 0,
     .nbErrors = 0,
 };
 // clang-format on

src/link/fstack.cpp

@@ -3,7 +3,7 @@
 #include <inttypes.h>
 #include <utility>
 
-#include "style.hpp"
+#include "backtrace.hpp"
 
 #include "link/warning.hpp"
 
@@ -30,51 +30,10 @@ std::vector<std::pair<std::string, uint32_t>> FileStackNode::backtrace(uint32_t
 	}
 }
 
-static void printNode(std::pair<std::string, uint32_t> const &node) {
-	style_Set(stderr, STYLE_CYAN, true);
-	fputs(node.first.c_str(), stderr);
-	style_Set(stderr, STYLE_CYAN, false);
-	fprintf(stderr, "(%" PRIu32 ")", node.second);
-}
-
 void FileStackNode::printBacktrace(uint32_t curLineNo) const {
-	std::vector<std::pair<std::string, uint32_t>> nodes = backtrace(curLineNo);
-	size_t n = nodes.size();
-
-	if (warnings.traceDepth == TRACE_COLLAPSE) {
-		fputs("   ", stderr); // Just three spaces; the fourth will be handled by the loop
-		for (size_t i = 0; i < n; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, " %s ", i == 0 ? "at" : "<-");
-			printNode(nodes[n - i - 1]);
-		}
-		putc('\n', stderr);
-	} else if (warnings.traceDepth == 0 || static_cast<size_t>(warnings.traceDepth) >= n) {
-		for (size_t i = 0; i < n; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
-			printNode(nodes[n - i - 1]);
-			putc('\n', stderr);
-		}
-	} else {
-		size_t last = warnings.traceDepth / 2;
-		size_t first = warnings.traceDepth - last;
-		size_t skipped = n - warnings.traceDepth;
-		for (size_t i = 0; i < first; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
-			printNode(nodes[n - i - 1]);
-			putc('\n', stderr);
-		}
-		style_Reset(stderr);
-		fprintf(stderr, "    ...%zu more%s\n", skipped, last ? "..." : "");
-		for (size_t i = n - last; i < n; ++i) {
-			style_Reset(stderr);
-			fputs("    <- ", stderr);
-			printNode(nodes[n - i - 1]);
-			putc('\n', stderr);
-		}
-	}
-
-	style_Reset(stderr);
+	trace_PrintBacktrace(
+	    backtrace(curLineNo),
+	    [](std::pair<std::string, uint32_t> const &node) { return node.first.c_str(); },
+	    [](std::pair<std::string, uint32_t> const &node) { return node.second; }
+	);
 }

src/link/lexer.cpp

@@ -9,9 +9,9 @@
 #include <stdio.h>
 #include <vector>
 
+#include "backtrace.hpp"
 #include "helpers.hpp"
 #include "itertools.hpp"
-#include "style.hpp"
 #include "util.hpp"
 
 #include "link/warning.hpp"
@@ -28,52 +28,12 @@ struct LexerStackEntry {
 
 static std::vector<LexerStackEntry> lexerStack;
 
-static void printStackEntry(LexerStackEntry const &context) {
-	style_Set(stderr, STYLE_CYAN, true);
-	fputs(context.path.c_str(), stderr);
-	style_Set(stderr, STYLE_CYAN, false);
-	fprintf(stderr, "(%" PRIu32 ")", context.lineNo);
-}
-
 void lexer_TraceCurrent() {
-	size_t n = lexerStack.size();
-
-	if (warnings.traceDepth == TRACE_COLLAPSE) {
-		fputs("   ", stderr); // Just three spaces; the fourth will be handled by the loop
-		for (size_t i = 0; i < n; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, " %s ", i == 0 ? "at" : "<-");
-			printStackEntry(lexerStack[n - i - 1]);
-		}
-		putc('\n', stderr);
-	} else if (warnings.traceDepth == 0 || static_cast<size_t>(warnings.traceDepth) >= n) {
-		for (size_t i = 0; i < n; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
-			printStackEntry(lexerStack[n - i - 1]);
-			putc('\n', stderr);
-		}
-	} else {
-		size_t last = warnings.traceDepth / 2;
-		size_t first = warnings.traceDepth - last;
-		size_t skipped = n - warnings.traceDepth;
-		for (size_t i = 0; i < first; ++i) {
-			style_Reset(stderr);
-			fprintf(stderr, "    %s ", i == 0 ? "at" : "<-");
-			printStackEntry(lexerStack[n - i - 1]);
-			putc('\n', stderr);
-		}
-		style_Reset(stderr);
-		fprintf(stderr, "    ...%zu more%s\n", skipped, last ? "..." : "");
-		for (size_t i = n - last; i < n; ++i) {
-			style_Reset(stderr);
-			fputs("    <- ", stderr);
-			printStackEntry(lexerStack[n - i - 1]);
-			putc('\n', stderr);
-		}
-	}
-
-	style_Reset(stderr);
+	trace_PrintBacktrace(
+	    lexerStack,
+	    [](LexerStackEntry const &context) { return context.path.c_str(); },
+	    [](LexerStackEntry const &context) { return context.lineNo; }
+	);
 }
 
 void lexer_IncludeFile(std::string &&path) {

src/link/main.cpp

@@ -10,6 +10,7 @@
 #include <string.h>
 #include <utility>
 
+#include "backtrace.hpp"
 #include "diagnostics.hpp"
 #include "extern/getopt.hpp"
 #include "helpers.hpp" // assume
@@ -295,21 +296,11 @@ int main(int argc, char *argv[]) {
 	// Parse options
 	for (int ch; (ch = musl_getopt_long_only(argc, argv, optstring, longopts, nullptr)) != -1;) {
 		switch (ch) {
-		case 'B': {
-			if (!strcasecmp(musl_optarg, "collapse")) {
-				warnings.traceDepth = TRACE_COLLAPSE;
-				break;
-			}
-			char *endptr;
-			warnings.traceDepth = strtoul(musl_optarg, &endptr, 0);
-			if (musl_optarg[0] == '\0' || *endptr != '\0') {
+		case 'B':
+			if (!trace_ParseTraceDepth(musl_optarg)) {
 				fatal("Invalid argument for option '-B'");
 			}
-			if (warnings.traceDepth >= UINT64_MAX) {
-				fatal("Argument for option '-B' is too large");
-			}
 			break;
-		}
 		case 'd':
 			options.isDmgMode = true;
 			options.isWRAM0Mode = true;

src/link/warning.cpp

@@ -26,7 +26,6 @@ Diagnostics<WarningLevel, WarningID> warnings = {
     },
     .paramWarnings = {},
     .state = DiagnosticsState<WarningID>(),
-    .traceDepth = 0,
     .nbErrors = 0,
 };
 // clang-format on