Enable IPv4 or IPv4/IPv6 stacks, Ethernet class (#695)

IPv4-only mode saves 20KB+ of flash memory.

Add some backwards compatibility with the global Arduino Ethernet
class when running in IPv4 only mode.

Fixes #687

* Speed P.IO build by not cloning 2GB of sources
* Document P.IO new option

.github/workflows/pull-request.yml

@@ -185,7 +185,14 @@ jobs:
     steps:
     - uses: actions/checkout@v3
       with:
-        submodules: 'recursive'
+        submodules: 'true'
+    - name: Initialize needed submodules
+      run: |
+        cd pico-sdk
+        git submodule update --init
+        cd ../libraries/Adafruit_TinyUSB_Arduino
+        git submodule update --init
+        cd ../..
     - name: Cache pip
       uses: actions/cache@v2
       with:

cores/rp2040/api/IPAddress.cpp

@@ -179,8 +179,10 @@ bool IPAddress::isValid(const char* arg) {
 	return IPAddress().fromString(arg);
 }
 
+namespace arduino {
 const IPAddress INADDR_ANY; // generic "0.0.0.0" for IPv4 & IPv6
 const IPAddress INADDR_NONE(255,255,255,255);
+};
 
 void IPAddress::clear() {
     (*this) = INADDR_ANY;

cores/rp2040/api/IPAddress.h

@@ -27,11 +27,14 @@
 #include <lwip/ip_addr.h>
 #include <lwip/ip4_addr.h>
 
-namespace arduino {
 
-#if !LWIP_IPV6
-struct ip_addr: ipv4_addr { };
-#endif // !LWIP_IPV6
+// forward declarations of global name space friend classes
+class EthernetClass;
+class DhcpClass;
+class DNSClient;
+
+
+namespace arduino {
 
 // to display a netif id with printf:
 #define NETIFID_STR        "%c%c%u"
@@ -48,8 +51,19 @@ struct ip_addr: ipv4_addr { };
 
 class IPAddress: public Printable {
     private:
-
+#if !LWIP_IPV6
+        // Ugly hack to allow Arduino Ethernet library to twiddle internal bits.
+        // This can only work in IPv4-only mode, of course.
+        union {
+            ip_addr_t _ip;
+            struct {
+                uint8_t bytes[4];
+            } _address;
+        };
+        static_assert(sizeof(_ip) == sizeof(_address), "IP_ADDR_T size != _ADDRESS size");
+#else
         ip_addr_t _ip;
+#endif
 
         // Access the raw byte array containing the address.  Because this returns a pointer
         // to the internal structure rather than a copy of the address this function should only
@@ -149,6 +163,10 @@ class IPAddress: public Printable {
         friend class DhcpClass;
         friend class DNSClient;
 
+        friend ::EthernetClass;
+        friend ::DhcpClass;
+        friend ::DNSClient;
+
         /*
                lwIP address compatibility
         */
@@ -167,7 +185,6 @@ class IPAddress: public Printable {
 
         bool isLocal () const { return ip_addr_islinklocal(&_ip); }
 
-#if LWIP_IPV6
 
         IPAddress(const ip_addr_t& lwip_addr) { ip_addr_copy(_ip, lwip_addr); }
         IPAddress(const ip_addr_t* lwip_addr) { ip_addr_copy(_ip, *lwip_addr); }
@@ -175,6 +192,7 @@ class IPAddress: public Printable {
         IPAddress& operator=(const ip_addr_t& lwip_addr) { ip_addr_copy(_ip, lwip_addr); return *this; }
         IPAddress& operator=(const ip_addr_t* lwip_addr) { ip_addr_copy(_ip, *lwip_addr); return *this; }
 
+#if LWIP_IPV6
         uint16_t* raw6()
         {
             setV6();

docs/platformio.rst

@@ -222,6 +222,18 @@ default Pico SDK USB stack. To change it, add
 Note that the special "No USB" setting is also supported, through the
 shortcut-define ``PIO_FRAMEWORK_ARDUINO_NO_USB``.
 
+IP Stack
+---------
+
+The lwIP stack can be configured to support only IPv4 (default) or additionally IPv6. To activate IPv6 support, add 
+
+.. code:: ini
+
+    ; IPv6
+    build_flags = -DPIO_FRAMEWORK_ARDUINO_ENABLE_IPV6
+
+to the ``platformio.ini``.
+
 
 Selecting a different core version
 ----------------------------------

libraries/lwIP_Ethernet/src/LwipIntfDev.h

@@ -179,7 +179,7 @@ int LwipIntfDev<RawDev>::hostByName(const char* aHostname, IPAddress& aResult, i
 #if LWIP_IPV4 && LWIP_IPV6
     err_t err = dns_gethostbyname_addrtype(aHostname, &addr, &_dns_found_callback, &cb, LWIP_DNS_ADDRTYPE_DEFAULT);
 #else
-    err_t err = dns_gethostbyname(aHostname, &addr, &wifi_dns_found_callback, &cb);
+    err_t err = dns_gethostbyname(aHostname, &addr, &_dns_found_callback, &cb);
 #endif
     if (err == ERR_OK) {
         aResult = IPAddress(&addr);

platform.txt

@@ -41,12 +41,11 @@ compiler.warning_flags.default=-Werror=return-type
 compiler.warning_flags.more=-Wall -Werror=return-type -Wno-ignored-qualifiers
 compiler.warning_flags.all=-Wall -Wextra -Werror=return-type -Wno-ignored-qualifiers
 
-compiler.netdefines=-DPICO_CYW43_ARCH_THREADSAFE_BACKGROUND=1 -DCYW43_LWIP=0 -DLWIP_IPV6=1 -DLWIP_IPV4=1 -DLWIP_IGMP=1 -DLWIP_CHECKSUM_CTRL_PER_NETIF=1
+compiler.netdefines=-DPICO_CYW43_ARCH_THREADSAFE_BACKGROUND=1 -DCYW43_LWIP=0 {build.lwipdefs} -DLWIP_IGMP=1 -DLWIP_CHECKSUM_CTRL_PER_NETIF=1
 compiler.defines={build.led} {build.usbstack_flags} -DCFG_TUSB_MCU=OPT_MCU_RP2040 -DUSB_VID={build.vid} -DUSB_PID={build.pid} '-DUSB_MANUFACTURER={build.usb_manufacturer}' '-DUSB_PRODUCT={build.usb_product}' {compiler.netdefines}
 compiler.includes="-iprefix{runtime.platform.path}/" "@{runtime.platform.path}/lib/platform_inc.txt" "-I{runtime.platform.path}/include"
 compiler.flags=-march=armv6-m -mcpu=cortex-m0plus -mthumb -ffunction-sections -fdata-sections {build.flags.exceptions} {build.flags.stackprotect}
 compiler.wrap="@{runtime.platform.path}/lib/platform_wrap.txt"
-compiler.libpico="{runtime.platform.path}/lib/libpico.a"
 compiler.libbearssl="{runtime.platform.path}/lib/libbearssl.a"
 
 compiler.c.cmd=arm-none-eabi-gcc
@@ -92,8 +91,9 @@ build.usbstack_flags=
 build.flags.libstdcpp=-lstdc++
 build.flags.exceptions=-fno-exceptions
 build.flags.stackprotect=
-
+build.libpico=libpico.a
 build.boot2=boot2_generic_03h_4_padded_checksum
+build.lwipdefs=-DLWIP_IPV6=0 -DLWIP_IPV4=1
 
 # Allow Pico boards do be auto-discovered by the IDE
 discovery.rp2040.pattern="{runtime.tools.pqt-python3.path}/python3" -I "{runtime.platform.path}/tools/discovery.py"
@@ -123,7 +123,7 @@ recipe.hooks.linking.prelink.1.pattern="{runtime.tools.pqt-python3.path}/python3
 recipe.hooks.linking.prelink.2.pattern="{compiler.path}{compiler.S.cmd}" {compiler.c.elf.flags} {compiler.c.elf.extra_flags} -c "{runtime.platform.path}/boot2/{build.boot2}.S" "-I{runtime.platform.path}/pico-sdk/src/rp2040/hardware_regs/include/" "-I{runtime.platform.path}/pico-sdk/src/common/pico_binary_info/include" -o "{build.path}/boot2.o"
 
 ## Combine gc-sections, archives, and objects
-recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" "-L{build.path}" {compiler.c.elf.flags} {compiler.c.elf.extra_flags} {compiler.ldflags} "-Wl,--script={build.path}/memmap_default.ld" "-Wl,-Map,{build.path}/{build.project_name}.map" -o "{build.path}/{build.project_name}.elf" -Wl,--start-group {object_files} "{build.path}/{archive_file}" "{build.path}/boot2.o" {compiler.libraries.ldflags} {compiler.libpico} {compiler.libbearssl} -lm -lc {build.flags.libstdcpp} -lc -Wl,--end-group
+recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" "-L{build.path}" {compiler.c.elf.flags} {compiler.c.elf.extra_flags} {compiler.ldflags} "-Wl,--script={build.path}/memmap_default.ld" "-Wl,-Map,{build.path}/{build.project_name}.map" -o "{build.path}/{build.project_name}.elf" -Wl,--start-group {object_files} "{build.path}/{archive_file}" "{build.path}/boot2.o" {compiler.libraries.ldflags} "{runtime.platform.path}/lib/{build.libpico}" {compiler.libbearssl} -lm -lc {build.flags.libstdcpp} -lc -Wl,--end-group
 
 ## Create output (UF2 file)
 recipe.objcopy.uf2.pattern="{runtime.tools.pqt-elf2uf2.path}/elf2uf2" "{build.path}/{build.project_name}.elf" "{build.path}/{build.project_name}.uf2"

tools/libpico/CMakeLists.txt

@@ -21,7 +21,7 @@ target_compile_definitions(pico PUBLIC
 	PICO_FLASH_SIZE_BYTES=16777216
 	PICO_XOSC_STARTUP_DELAY_MULTIPLIER=64
         LWIP_IPV4=1
-        LWIP_IPV6=1
+        LWIP_IPV6=${IPV6}
         LWIP_UDP=1
         LWIP_IGMP=1
         LWIP_CHECKSUM_CTRL_PER_NETIF=1

tools/libpico/make-libpico.sh

@@ -8,7 +8,7 @@ export PATH="$(cd ../../system/arm-none-eabi/bin; pwd):$PATH"
 rm -rf build
 mkdir build
 cd build
-cmake ..
+cmake .. -DIPV6=0
 make -j
 
 # Put everything in its place
@@ -17,6 +17,14 @@ mv generated/pico_base/pico/version.h ../../../include/pico_base/pico/.
 cp ../lwipopts.h ../../../include/.
 cp ../tusb_config.h ../../../include/.
 
+cd ..
+rm -rf build
+mkdir build
+cd build
+cmake .. -DIPV6=1
+make -j
+mv libpico.a ../../../lib/libpico-ipv6.a
+
 rm -rf boot
 mkdir boot
 cd boot

tools/makeboards.py

@@ -83,6 +83,14 @@ def BuildWithoutUSBStack(name):
     print("%s.menu.usbstack.nousb=No USB" % (name))
     print('%s.menu.usbstack.nousb.build.usbstack_flags="-DNO_USB -DDISABLE_USB_SERIAL -I{runtime.platform.path}/tools/libpico"' % (name))
 
+def BuildIPStack(name):
+    print("%s.menu.ipstack.ipv4only=IPv4 Only" % (name))
+    print('%s.menu.ipstack.ipv4only.build.libpico=libpico.a' % (name))
+    print('%s.menu.ipstack.ipv4only.build.lwipdefs=-DLWIP_IPV6=0 -DLWIP_IPV4=1' % (name))
+    print("%s.menu.ipstack.ipv4ipv6=IPv4 and IPv6" % (name))
+    print('%s.menu.ipstack.ipv4ipv6.build.libpico=libpico-ipv6.a' % (name))
+    print('%s.menu.ipstack.ipv4ipv6.build.lwipdefs=-DLWIP_IPV6=1 -DLWIP_IPV4=1' % (name))
+
 def BuildHeader(name, vendor_name, product_name, vidtouse, pidtouse, vid, pid, pwr, boarddefine, variant, uploadtool, flashsize, ramsize, boot2):
     prettyname = vendor_name + " " + product_name
     print()
@@ -133,7 +141,7 @@ def BuildGlobalMenuList():
     print("menu.dbglvl=Debug Level")
     print("menu.boot2=Boot Stage 2")
     print("menu.usbstack=USB Stack")
-
+    print("menu.ipstack=IP Stack")
 
 def MakeBoard(name, vendor_name, product_name, vid, pid, pwr, boarddefine, flashsizemb, boot2):
     for a, b, c in [ ["", "", "uf2conv"], ["picoprobe", " (Picoprobe)", "picoprobe"], ["picodebug", " (pico-debug)", "picodebug"]]:
@@ -171,6 +179,7 @@ def MakeBoard(name, vendor_name, product_name, vid, pid, pwr, boarddefine, flash
             BuildWithoutUSBStack(n)
         else:
             BuildUSBStack(n)
+        BuildIPStack(n)
         if name == "generic":
             BuildBoot(n)
     MakeBoardJSON(name, vendor_name, product_name, vid, pid, pwr, boarddefine, flashsizemb, boot2)

tools/platformio-build.py

@@ -79,6 +79,12 @@ env.Replace(
     SIZEPROGREGEXP=r"^(?:\.boot2|\.text|\.data|\.rodata|\.text.align|\.ARM.exidx)\s+(\d+).*"
 )
 
+# pico support library depends on ipv6 enable/disable
+if "PIO_FRAMEWORK_ARDUINO_ENABLE_IPV6" in flatten_cppdefines:
+    libpico = File(os.path.join(FRAMEWORK_DIR, "lib", "libpico-ipv6.a"))
+else:
+    libpico = File(os.path.join(FRAMEWORK_DIR, "lib", "libpico.a"))
+
 env.Append(
     ASFLAGS=env.get("CCFLAGS", [])[:],
 
@@ -106,13 +112,6 @@ env.Append(
         "ARDUINO_ARCH_RP2040",
         ("F_CPU", "$BOARD_F_CPU"),
         ("BOARD_NAME", '\\"%s\\"' % env.subst("$BOARD")),
-        # LWIP-related
-        ("PICO_CYW43_ARCH_THREADSAFE_BACKGROUND", 1),
-        ("CYW43_LWIP", 0),
-        ("LWIP_IPV6", 1),
-        ("LWIP_IPV4", 1),
-        ("LWIP_IGMP", 1),
-        ("LWIP_LWIP_CHECKSUM_CTRL_PER_NETIF", 1),
     ],
 
     CPPPATH=[
@@ -147,7 +146,7 @@ env.Append(
 
     # link lib/libpico.a by full path, ignore libstdc++
     LIBS=[
-        File(os.path.join(FRAMEWORK_DIR, "lib", "libpico.a")),
+        libpico,
         File(os.path.join(FRAMEWORK_DIR, "lib", "libbearssl.a")),
         "m", "c", stdcpp_lib, "c"]
 )
@@ -228,15 +227,19 @@ def configure_usb_flags(cpp_defines):
     board.update("build.hwids", hw_ids)
     board.update("upload.maximum_ram_size", ram_size)
 
-def configure_network_flags():
+def configure_network_flags(cpp_defines):
     env.Append(CPPDEFINES=[
         ("PICO_CYW43_ARCH_THREADSAFE_BACKGROUND", 1),
         ("CYW43_LWIP", 0),
-        ("LWIP_IPV6", 1),
         ("LWIP_IPV4", 1),
         ("LWIP_IGMP", 1),
         ("LWIP_CHECKSUM_CTRL_PER_NETIF", 1)
     ])
+    if "PIO_FRAMEWORK_ARDUINO_ENABLE_IPV6" in cpp_defines:
+        env.Append(CPPDEFINES=[("LWIP_IPV6", 1)])
+    else:
+        env.Append(CPPDEFINES=[("LWIP_IPV6", 0)])
+
 #
 # Process configuration flags
 #
@@ -255,7 +258,7 @@ if not "USE_TINYUSB" in cpp_defines:
         )
 # configure USB stuff
 configure_usb_flags(cpp_defines)
-configure_network_flags()
+configure_network_flags(cpp_defines)
 
 # ensure LWIP headers are in path after any TINYUSB distributed versions, also PicoSDK USB path headers
 env.Append(CPPPATH=[os.path.join(FRAMEWORK_DIR, "include")])