svg-flatten: Add wasmtime support

5 files changed, 100 insertions, 28 deletions

diff --git a/svg-flatten/Makefile b/svg-flatten/Makefile
index fc5820f..94dab9b 100644
--- a/svg-flatten/Makefile
+++ b/svg-flatten/Makefile
@@ -6,10 +6,17 @@ PKG_CONFIG ?= pkg-config
 PYTHON3 ?= python3
 
 BUILDDIR ?= build
+CACHEDIR ?= cache
 PREFIX ?= /usr/local
-UPSTREAM_DIR ?= ../upstream
+UPSTREAM_DIR ?= upstream
 
-SOURCES := src/svg_color.cpp \
+WASI_SDK ?= wasi-sdk-11.0
+WASI_SDK_URL ?= https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-11/wasi-sdk-11.0-linux.tar.gz
+WASI_SDK_PATH ?= $(CACHEDIR)/$(WASI_SDK)
+WASI_CXX ?= $(WASI_SDK_PATH)/bin/clang++ --sysroot=$(WASI_SDK_PATH)/share/wasi-sysroot
+
+SOURCES := \
+	src/svg_color.cpp \
 	src/svg_doc.cpp \
 	src/svg_geom.cpp \
 	src/svg_import_util.cpp \
@@ -47,28 +54,47 @@ STB_INCLUDES		?= -isystem$(UPSTREAM_DIR)/stb
 INCLUDES := -Iinclude -Isrc $(CLIPPER_INCLUDES) $(VORONOI_INCLUDES) $(POISSON_INCLUDES) $(BASE64_INCLUDES) $(ARGAGG_INCLUDES) $(CAVC_INCLUDES) $(SUBPROCESS_INCLUDES) $(MINUNIT_INCLUDES) $(STB_INCLUDES)
 
 CXXFLAGS := -std=c++2a -g -Wall -Wextra -O2
-LDFLAGS := -lm -lstdc++ -lstdc++fs # for debian's ancient compilers
+LDFLAGS := -lm -lstdc++
 
-PKG_CONFIG_DEPS := 
 ifdef USE_SYSTEM_PUGIXML
-	CXXFLAGS += $(shell $(PKG_CONFIG) --cflags pugixml)
-	LDFLAGS += $(shell $(PKG_CONFIG) --libs pugixml)
+	HOST_CXXFLAGS := $(CXXFLAGS) $(shell $(PKG_CONFIG) --cflags pugixml)
+	HOST_LDFLAGS := $(LDFLAGS) $(shell $(PKG_CONFIG) --libs pugixml)
+	HOST_SOURCES := $(SOURCES)
+	HOST_INCLUDES := $(INCLUDES)
 else
-	SOURCES += $(PUGIXML_SOURCES)
-	INCLUDES += $(PUGIXML_INCLUDES)
+	HOST_CXXFLAGS := $(CXXFLAGS)
+	HOST_LDFLAGS := $(LDFLAGS)
+	HOST_SOURCES := $(SOURCES) $(PUGIXML_SOURCES)
+	HOST_INCLUDES := $(INCLUDES) $(PUGIXML_INCLUDES)
 endif
 
-TARGET := svg-flatten
+HOST_LDFLAGS += -lstdc++fs # for debian's ancient compilers
+
+WASI_CXXFLAGS ?= -DNOFORK -DNOTHROW -DWASI -DPUGIXML_NO_EXCEPTIONS -fno-exceptions $(CXXFLAGS)
+
+BINARY := svg-flatten
+
+all: $(BUILDDIR)/$(BINARY)
 
-all: $(BUILDDIR)/$(TARGET)
+$(CACHEDIR)/$(WASI_SDK):
+	mkdir -p $(dir $@)
+	cd $(dir $@); curl -L ${WASI_SDK_URL} | tar xzf -
 
-$(BUILDDIR)/%.o: %.cpp
+$(BUILDDIR)/wasi/%.o: %.cpp $(CACHEDIR)/$(WASI_SDK) 
 	@mkdir -p $(dir $@) 
-	$(CXX) -c $(CXXFLAGS) $(CXXFLAGS) $(INCLUDES) -o $@ $^
+	$(WASI_CXX) -c $(WASI_CXXFLAGS) $(INCLUDES) $(PUGIXML_INCLUDES) -o $@ $<
 
-$(BUILDDIR)/$(TARGET): $(SOURCES:%.cpp=$(BUILDDIR)/%.o)
+$(BUILDDIR)/$(BINARY).wasm: $(patsubst %.cpp,$(BUILDDIR)/wasi/%.o,$(SOURCES) $(PUGIXML_SOURCES))
+	@mkdir -p $(dir $@)
+	$(WASI_CXX) $(WASI_CXXFLAGS) -o $@ $^ $(LDFLAGS)
+
+$(BUILDDIR)/host/%.o: %.cpp
+	@mkdir -p $(dir $@) 
+	$(CXX) -c $(HOST_CXXFLAGS) $(HOST_CXXFLAGS) $(HOST_INCLUDES) -o $@ $<
+
+$(BUILDDIR)/$(BINARY): $(HOST_SOURCES:%.cpp=$(BUILDDIR)/host/%.o)
 	@mkdir -p $(dir $@) 
-	$(CXX) $(CXXFLAGS) -o $@ $^ $(LDFLAGS)
+	$(CXX) $(HOST_CXXFLAGS) -o $@ $^ $(HOST_LDFLAGS)
 
 $(BUILDDIR)/nopencv-test: src/test/nopencv_test.cpp src/nopencv.cpp src/util.cpp
 	@mkdir -p $(dir $@) 
@@ -82,8 +108,12 @@ tests: $(BUILDDIR)/nopencv-test
 
 .PHONY: install
 install:
-	$(INSTALL) $(BUILDDIR)/$(TARGET) $(PREFIX)/bin
+	$(INSTALL) $(BUILDDIR)/$(BINARY) $(PREFIX)/bin
 	
 .PHONY: clean
 clean:
 	rm -rf $(BUILDDIR)
+
+.PHONY: mrproper
+mrproper: clean
+	rm -rf $(CACHEDIR)
diff --git a/svg-flatten/src/main.cpp b/svg-flatten/src/main.cpp
index 8512547..2ebcfe9 100644
--- a/svg-flatten/src/main.cpp
+++ b/svg-flatten/src/main.cpp
@@ -3,6 +3,7 @@
 #include <cstdio>
 #include <filesystem>
 #include <iostream>
+#include <iomanip>
 #include <fstream>
 #include <algorithm>
 #include <string>
@@ -17,6 +18,34 @@ using argagg::parser;
 using namespace std;
 using namespace gerbolyze;
 
+string temp_file_path(const char *suffix) {
+    ifstream rnd;
+    rnd.open("/dev/urandom", ios::in | ios::binary);
+
+    char fn_buf[8];
+    rnd.read(fn_buf, sizeof(fn_buf));
+
+    if (rnd.rdstate()) {
+        cerr << "Error getting random data for temporary file name" << endl;
+        abort();
+    }
+
+    ostringstream out;
+    out << "tmp_";
+    for (size_t i=0; i<sizeof(fn_buf); i++) {
+        out << setfill('0') << setw(2) << setbase(16) << static_cast<int>(fn_buf[i] & 0xff);
+    }
+    out << suffix;
+
+    cerr << "out \"" << out.str() << "\"" << endl;
+#ifndef WASI
+    filesystem::path base = filesystem::temp_directory_path();
+    return (base / out.str()).native();
+#else
+    return "/tmp/" + out.str();
+#endif
+}
+
 int main(int argc, char **argv) {
     parser argparser {{
             {"help", {"-h", "--help"},
@@ -114,15 +143,7 @@ int main(int argc, char **argv) {
         << endl;
 
     argagg::parser_results args;
-    try {
-        args = argparser.parse(argc, argv);
-    } catch (const std::exception& e) {
-        argagg::fmt_ostream fmt(cerr);
-        fmt << usage.str() << argparser << '\n'
-            << "Encountered exception while parsing arguments: " << e.what()
-            << '\n';
-        return EXIT_FAILURE;
-    }
+    args = argparser.parse(argc, argv);
 
     if (args["help"]) {
         argagg::fmt_ostream fmt(cerr);
@@ -267,8 +288,8 @@ int main(int argc, char **argv) {
         transform(ending.begin(), ending.end(), ending.begin(), [](unsigned char c){ return std::tolower(c); }); /* c++ yeah */
     }
     
-    filesystem::path barf = { filesystem::temp_directory_path() /= (std::tmpnam(nullptr) + string(".svg")) };
-    filesystem::path frob = { filesystem::temp_directory_path() /= (std::tmpnam(nullptr) + string(".svg")) };
+    string barf =  temp_file_path(".svg");
+    string frob = temp_file_path(".svg");
 
     bool is_svg = args["force_svg"] || (ending == ".svg" && !args["force_png"]);
     if (!is_svg) {
@@ -352,10 +373,15 @@ int main(int argc, char **argv) {
         }
         string dpi_str = to_string(dpi);
         
+#ifndef NOFORK
         const char *command_line[] = {nullptr, "--keep-named-groups", "--dpi", dpi_str.c_str(), barf.c_str(), frob.c_str(), nullptr};
         if (run_cargo_command("usvg", command_line, "USVG")) {
             return EXIT_FAILURE;
         }
+#else
+        cerr << "Error: The caller of svg-flatten (you?) must use --no-usvg and run usvg externally since wasi does not yet support fork/exec." << endl;
+        return EXIT_FAILURE;
+#endif
     }
 
     VectorizerSelectorizer vec_sel(vectorizer, args["vectorizer_map"] ? args["vectorizer_map"].as<string>() : "");
diff --git a/svg-flatten/src/svg_import_util.cpp b/svg-flatten/src/svg_import_util.cpp
index cb60482..85db3ad 100644
--- a/svg-flatten/src/svg_import_util.cpp
+++ b/svg-flatten/src/svg_import_util.cpp
@@ -61,6 +61,11 @@ string gerbolyze::parse_data_iri(const string &data_url) {
     size_t b64_begin = data_url.find_first_not_of(" ", foo + strlen("base64,"));
     assert(b64_begin != string::npos);
 
-    return base64_decode(data_url.substr(b64_begin));
+    bool err_out;
+    string out = base64_decode(data_url.substr(b64_begin), false, &err_out);
+
+    if (err_out)
+      return "";
+    return out;
 }
 
diff --git a/svg-flatten/src/util.cpp b/svg-flatten/src/util.cpp
index e88f4e9..d9a5a09 100644
--- a/svg-flatten/src/util.cpp
+++ b/svg-flatten/src/util.cpp
@@ -1,16 +1,19 @@
 
-#include <pwd.h>
 #include <sys/types.h>
 #include <string>
 #include <iostream>
 
+#ifndef NOFORK
+#include <pwd.h>
 #include <subprocess.h>
+#endif
 #include <filesystem>
 
 #include "util.h"
 
 using namespace std;
 
+#ifndef NOFORK
 int gerbolyze::run_cargo_command(const char *cmd_name, const char *cmdline[], const char *envvar) {
     const char *homedir;
     if ((homedir = getenv("HOME")) == NULL) {
@@ -81,4 +84,11 @@ int gerbolyze::run_cargo_command(const char *cmd_name, const char *cmdline[], co
 
     return 0;
 }
+#else
+int gerbolyze::run_cargo_command(const char *cmd_name, const char *cmdline[], const char *envvar) {
+    (void) cmd_name, (void) cmdline, (void) envvar;
+    cerr << "Error: Cannot spawn " << cmd_name << " subprocess since binary was built with fork/exec disabled (-DNOFORK=1)" << endl;
+    return EXIT_FAILURE;
+}
+#endif
 
diff --git a/svg-flatten/upstream b/svg-flatten/upstream
new file mode 120000
index 0000000..f84a283
--- /dev/null
+++ b/svg-flatten/upstream
@@ -0,0 +1 @@
+../upstream
\ No newline at end of file