Sketch emulation on host (#5342)

* WIP compile examples on host with 'make examples'

* WIP bufferize tcp input

* WIP Makefile

* WIP network to rework, tcp/udp to factorize, udp addresses broken

* minor changes to the core

* WIP basic udp working

* WIP mdns

* WIP mcast receiving, not sending

* WIP mdns OK

* beta version

* SSL + doc

* update travis host test command

* licenses

* typo

* doc: arduino builder is not around: declare functions before calling them

* fix with latest SSL PR, compile in 32 bits mode

* fix make clean

* make -m32 optional

* 32bits compiler ability tester

* WIP

* WIP (fix 1 vtable error, still another one to hunt with using spiffs)

* example astyle

* fix os_printf_plus

* load / save mock spiffs

* fix style

* fix using spiffs/mock

* don't mess ram

* update doc

* remove leftover

* optimization -Os except for CI, rename ARCH32 to FORCE32

* revert useless cast (not even compiled)

* remove unused function

* use proper type for pointer arithmetics

* makefile: sketch object and cpp file moved to bin/ directories
easier to clean, and IDE don't like them

* changes for review

* make use of %zd

* less verbose makefile by default (option)

* update readme

tests/host/common/spiffs_mock.cpp

@@ -1,14 +1,14 @@
 /*
  spiffs_mock.cpp - SPIFFS HAL mock for host side testing
  Copyright © 2016 Ivan Grokhotkov
- 
+
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
- 
+
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
 */
@@ -22,6 +22,13 @@
 
 #include <spiffs_api.h>
 
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#define SPIFFS_FILE_NAME "spiffs.bin"
+
 extern "C"
 {
     static uint32_t s_phys_addr = 0;
@@ -33,32 +40,89 @@ extern "C"
 
 FS SPIFFS(nullptr);
 
-SpiffsMock::SpiffsMock(size_t fs_size, size_t fs_block, size_t fs_page)
+SpiffsMock::SpiffsMock(size_t fs_size, size_t fs_block, size_t fs_page, bool storage)
 {
-    m_fs.resize(fs_size, 0xff);
+    fprintf(stderr, "SPIFFS: %zd bytes\n", fs_size);
+
+    m_storage = storage;
+    m_fs = new uint8_t[m_fs_size = fs_size];
+    memset(&m_fs[0], 0xff, m_fs_size);
+
     s_phys_addr  = 0;
     s_phys_size  = static_cast<uint32_t>(fs_size);
     s_phys_page  = static_cast<uint32_t>(fs_page);
     s_phys_block = static_cast<uint32_t>(fs_block);
-    s_phys_data  = m_fs.data();
+    s_phys_data  = &m_fs[0];
     reset();
 }
 
 void SpiffsMock::reset()
 {
     SPIFFS = FS(FSImplPtr(new SPIFFSImpl(0, s_phys_size, s_phys_page, s_phys_block, 5)));
+    if (m_storage)
+        load();
 }
-    
+
 SpiffsMock::~SpiffsMock()
 {
+    if (m_storage)
+        save();
     s_phys_addr  = 0;
     s_phys_size  = 0;
     s_phys_page  = 0;
     s_phys_block = 0;
     s_phys_data  = nullptr;
+    delete [] m_fs;
+    m_fs = nullptr;
+    m_fs_size = 0;
     SPIFFS = FS(FSImplPtr(nullptr));
 }
 
+void SpiffsMock::load ()
+{
+    if (!m_fs_size)
+        return;
+
+    const char* fname = getenv("SPIFFS_PATH");
+    if (!fname)
+        fname = DEFAULT_SPIFFS_FILE_NAME;
+    int fs = ::open(SPIFFS_FILE_NAME, O_RDONLY);
+    if (fs == -1)
+    {
+        fprintf(stderr, "SPIFFS: loading '%s': %s\n", fname, strerror(errno));
+        return;
+    }
+    fprintf(stderr, "SPIFFS: loading %zi bytes from '%s'\n", m_fs_size, fname);
+    if (::read(fs, &m_fs[0], m_fs_size) != (ssize_t)m_fs_size)
+        fprintf(stderr, "SPIFFS: reading %zi bytes: %s\n", m_fs_size, strerror(errno));
+    ::close(fs);
+}
+
+void SpiffsMock::save ()
+{
+    if (!m_fs_size)
+        return;
+
+    const char* fname = getenv("SPIFFS_PATH");
+    if (!fname)
+        fname = DEFAULT_SPIFFS_FILE_NAME;
+    int fs = ::open(SPIFFS_FILE_NAME, O_CREAT | O_TRUNC | O_WRONLY, 0644);
+    if (fs == -1)
+    {
+        fprintf(stderr, "SPIFFS: saving '%s': %s\n", fname, strerror(errno));
+        return;
+    }
+    fprintf(stderr, "SPIFFS: saving %zi bytes to '%s'\n", m_fs_size, fname);
+
+// this can be a valgrind error, I don't understand how it happens
+//for (size_t i = 0; i < m_fs_size; i++) printf("\r%zd:%d   ", i, (int)m_fs[i]);
+
+    if (::write(fs, &m_fs[0], m_fs_size) != (ssize_t)m_fs_size)
+        fprintf(stderr, "SPIFFS: writing %zi bytes: %s\n", m_fs_size, strerror(errno));
+    if (::close(fs) == -1)
+        fprintf(stderr, "SPIFFS: closing %s: %s\n", fname, strerror(errno));
+}
+
 int32_t spiffs_hal_read(uint32_t addr, uint32_t size, uint8_t *dst) {
     memcpy(dst, s_phys_data + addr, size);
     return SPIFFS_OK;