Add build and run support for FreeBSD OS, and potentially other BSD O…

…Ses (#476)

README.md

@@ -33,7 +33,7 @@ For more information, check out our
 
 ## Installation and Use
 
-Currently, we support Windows (7 or later), Linux, and macOS. An installed version of RetDec requires approximately 4 GB of free disk space.
+Currently, we support Windows (7 or later), Linux, macOS, and (experimental) FreeBSD. An installed version of RetDec requires approximately 4 GB of free disk space.
 
 ### Windows
 
@@ -91,6 +91,21 @@ Currently, we support Windows (7 or later), Linux, and macOS. An installed versi
 
    For more information, run `retdec-decompiler.py` with `--help`.
 
+### FreeBSD
+
+1. There are currently no pre-built "ports" packages for FreeBSD. You will have to build and install the decompiler by yourself. The process is described below.
+
+2. After you have built the decompiler, you may need to install the following packages and execute the following command:
+* `sudo pkg install python37 bison autotools`
+* `sudo ln -s /usr/local/bin/python3.7 /usr/local/bin/python3`
+
+3. Now, you are all set to run the decompiler. To decompile a binary file named `test.exe`, run
+
+    ```
+    $RETDEC_INSTALL_DIR/bin/retdec-decompiler.py test.exe
+    ```
+   For more information, run `retdec-decompiler.py` with `--help`.
+
 ## Build and Installation
 
 This section describes a local build and installation of RetDec. Instructions for Docker are given in the next section.
@@ -154,6 +169,21 @@ Packages should be preferably installed via [Homebrew](https://brew.sh).
 * [autotools](https://en.wikipedia.org/wiki/GNU_Build_System) ([autoconf](https://www.gnu.org/software/autoconf/autoconf.html), [automake](https://www.gnu.org/software/automake/), and [libtool](https://www.gnu.org/software/libtool/))
 * Optional: [Doxygen](http://www.stack.nl/~dimitri/doxygen/) and [Graphviz](http://www.graphviz.org/) for generating API documentation
 
+#### FreeBSD
+
+Packages should be installed via FreeBSDs pre-compiled package repository using the `pkg` command OR built from scratch using the `ports` database method.
+
+* Full "pkg" tool instructions [handbook pkg method](https://www.freebsd.org/doc/handbook/pkgng-intro.html)
+  * `pkg install cmake python37 bison git autotools`
+OR
+* Full "ports" instructions [handbook ports method](https://www.freebsd.org/doc/handbook/ports-using.html)
+  * `portsnap fetch`
+  * `portsnap extract`
+* For example "cmake" would be
+  * `whereis cmake`
+  * `cd /usr/ports/devel/cmake`
+  * `make install clean`
+
 ### Process
 
 Note: Although RetDec now supports a system-wide installation ([#94](https://github.com/avast-tl/retdec/issues/94)), unless you use your distribution's package manager to install it, we recommend installing RetDec locally into a designated directory. The reason for this is that uninstallation will be easier as you will only need to remove a single directory. To perform a local installation, run `cmake` with the `-DCMAKE_INSTALL_PREFIX=<path>` parameter, where `<path>` is directory into which RetDec will be installed (e.g. `$HOME/projects/retdec-install` on Linux and macOS, and `C:\projects\retdec-install` on Windows).
@@ -186,6 +216,22 @@ Note: Although RetDec now supports a system-wide installation ([#94](https://git
   * `cmake .. -DCMAKE_INSTALL_PREFIX=<path>`
   * `make -jN` (`N` is the number of CPU cores to use for parallel build)
   * `make install`
+* FreeBSD:
+  * `sudo pkg install git cmake`
+  * `git clone https://github.com/avast-tl/retdec`
+  * `cd retdec`
+  * `mkdir build && cd build`
+  * ```sh
+    # FreeBSD (and other BSDs) do need cmake, python3, bison, git, autotools. Flex and perl are pre-installed in the OS but check versions.
+    # Later versions may be available for each of the packages.
+    # See what is installed:
+    sudo pkg info cmake python37 bison autotools
+    # Install/upgrade them
+    sudo pkg install cmake python37 bison autotools
+    ```
+  * `cmake .. -DCMAKE_INSTALL_PREFIX=<path>`
+  * `make -jN` (`N` is the number of CPU cores to use for parallel build)
+  * `make install`
 
 You have to pass the following parameters to `cmake`:
 * `-DCMAKE_INSTALL_PREFIX=<path>` to set the installation path to `<path>`. Quote the path if you are using backslashes on Windows (e.g. `-DCMAKE_INSTALL_PREFIX="C:\retdec"`).

include/retdec/utils/os.h

@@ -11,14 +11,19 @@
 // Windows, macOS, and Linux.
 #if defined(__WIN) || defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__)
 	#define OS_WINDOWS
-#elif defined(__APPLE__)
-	#define OS_MACOS
 #else
-	#define OS_LINUX
+	#include <sys/param.h>
+	#if defined(__APPLE__)
+		#define OS_MACOS
+	#elif defined(BSD)
+		#define OS_BSD
+	#else
+		#define OS_LINUX
+	#endif
 #endif
 
 // It is also useful to know whether the operating system is POSIX compliant.
-#if defined(OS_MACOS) || defined(OS_LINUX)
+#if defined(OS_MACOS) || defined(OS_LINUX) || defined(OS_BSD)
 	#define OS_POSIX
 #endif
 

src/utils/memory.cpp

@@ -6,10 +6,11 @@
 
 #include "retdec/utils/memory.h"
 #include "retdec/utils/os.h"
+#include <cstddef>
 
 #ifdef OS_WINDOWS
 	#include <windows.h>
-#elif defined(OS_MACOS)
+#elif defined(OS_MACOS) || defined(OS_BSD)
 	#include <sys/types.h>
 	#include <sys/sysctl.h>
 #else
@@ -32,7 +33,7 @@ namespace {
 */
 bool limitSystemMemoryOnPOSIX(std::size_t limit) {
 	struct rlimit rl = {
-		.rlim_cur = limit,        // Soft limit.
+		.rlim_cur = static_cast<rlim_t>(limit),        // Soft limit.
 		.rlim_max = RLIM_INFINITY // Hard limit (ceiling for rlim_cur).
 	};
 	auto rc = setrlimit(RLIMIT_AS, &rl);
@@ -119,6 +120,30 @@ bool limitSystemMemoryOnMacOS(std::size_t limit) {
 	return limitSystemMemoryOnPOSIX(limit);
 }
 
+#elif defined(OS_BSD)
+
+/**
+* @brief Implementation of @c getTotalSystemMemory() on *BSD.
+*
+* AKA FreeBSD, DragonFly, NetBSD, OpenBSD, TrueOS, PCBSD
+*/
+std::size_t getTotalSystemMemoryOnBSD() {
+	int what[] = { CTL_HW, HW_PHYSMEM };
+	std::size_t value = 0;
+	std::size_t length = sizeof(value);
+	auto rc = sysctl(what, 2, &value, &length, nullptr, 0);
+	return rc != -1 ? value : 0;
+}
+
+/**
+* @brief Implementation of @c limitSystemMemory() on *BSD.
+*
+* AKA FreeBSD, DragonFly, NetBSD, OpenBSD, TrueOS, PCBSD
+*/
+bool limitSystemMemoryOnBSD(std::size_t limit) {
+	return limitSystemMemoryOnPOSIX(limit);
+}
+
 #else
 
 /*
@@ -151,6 +176,8 @@ std::size_t getTotalSystemMemory() {
 	return getTotalSystemMemoryOnWindows();
 #elif defined(OS_MACOS)
 	return getTotalSystemMemoryOnMacOS();
+#elif defined(OS_BSD)
+	return getTotalSystemMemoryOnBSD();
 #else
 	return getTotalSystemMemoryOnLinux();
 #endif
@@ -175,6 +202,8 @@ bool limitSystemMemory(std::size_t limit) {
 	return limitSystemMemoryOnWindows(limit);
 #elif defined(OS_MACOS)
 	return limitSystemMemoryOnMacOS(limit);
+#elif defined(OS_BSD)
+	return limitSystemMemoryOnBSD(limit);
 #else
 	return limitSystemMemoryOnLinux(limit);
 #endif