Add LZ4_FREESTANDING test on Linux x86-64 platform

Also added tests/Makefile entry "test-freestanding".

3 files changed, 244 insertions, 3 deletions

diff --git a/tests/.gitignore b/tests/.gitignore
index 5337fdbd..c7d8f19b 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -14,6 +14,7 @@ checkFrame
 decompress-partial
 decompress-partial-usingDict
 abiTest
+freestanding
 
 # test artefacts
 tmp*
diff --git a/tests/Makefile b/tests/Makefile
index 4b6ea489..33309b45 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -56,7 +56,7 @@ NB_LOOPS     ?= -i1
 .PHONY: default
 default: all
 
-all: fullbench fuzzer frametest roundTripTest datagen checkFrame decompress-partial
+all: fullbench fuzzer frametest roundTripTest datagen checkFrame decompress-partial freestanding
 
 all32: CFLAGS+=-m32
 all32: all
@@ -115,6 +115,9 @@ decompress-partial: lz4.o decompress-partial.c
 decompress-partial-usingDict: lz4.o decompress-partial-usingDict.c
 	$(CC) $(FLAGS) $^ -o $@$(EXT)
 
+freestanding: freestanding.c
+	$(CC) -ffreestanding -nostdlib $^ -o $@$(EXT)
+
 .PHONY: clean
 clean:
 	@$(MAKE) -C $(LZ4DIR) $@ > $(VOID)
@@ -127,7 +130,7 @@ clean:
         fasttest$(EXT) roundTripTest$(EXT) \
         datagen$(EXT) checkTag$(EXT) \
         frameTest$(EXT) decompress-partial$(EXT) \
-        abiTest$(EXT) \
+        abiTest$(EXT) freestanding$(EXT) \
         lz4_all.c
 	@$(RM) -rf $(TESTDIR)
 	@echo Cleaning completed
@@ -179,7 +182,7 @@ list:
 check: test-lz4-essentials
 
 .PHONY: test
-test: test-lz4 test-lz4c test-frametest test-fullbench test-fuzzer test-amalgamation listTest test-decompress-partial
+test: test-lz4 test-lz4c test-frametest test-fullbench test-fuzzer test-amalgamation listTest test-decompress-partial test-freestanding
 
 .PHONY: test32
 test32: CFLAGS+=-m32
@@ -606,4 +609,10 @@ test-decompress-partial : decompress-partial decompress-partial-usingDict
 	@echo "\n ---- test decompress-partial-usingDict ----"
 	./decompress-partial-usingDict$(EXT)
 
+test-freestanding: freestanding
+	@echo "\n ---- test freestanding ----"
+	./freestanding$(EXT)
+	strace ./freestanding$(EXT)
+	ltrace ./freestanding$(EXT)
+
 endif
diff --git a/tests/freestanding.c b/tests/freestanding.c
new file mode 100644
index 00000000..27813582
--- /dev/null
+++ b/tests/freestanding.c
@@ -0,0 +1,231 @@
+// Basic test for LZ4_FREESTANDING
+
+// $ gcc -ffreestanding -nostdlib freestanding.c && ./a.out || echo $?
+
+// $ strace ./a.out
+// execve("./a.out", ["./a.out"], 0x7fffaf5fa580 /* 22 vars */) = 0
+// brk(NULL)                               = 0x56536f4fe000
+// arch_prctl(0x3001 /* ARCH_??? */, 0x7fffc9e74950) = -1 EINVAL (Invalid argument)
+// mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fd5c9c2b000
+// access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
+// arch_prctl(ARCH_SET_FS, 0x7fd5c9c2bc40) = 0
+// set_tid_address(0x7fd5c9c2bf10)         = 381
+// set_robust_list(0x7fd5c9c2bf20, 24)     = 0
+// rseq(0x7fd5c9c2c5e0, 0x20, 0, 0x53053053) = 0
+// mprotect(0x56536ea63000, 4096, PROT_READ) = 0
+// exit(0)                                 = ?
+// +++ exited with 0 +++
+
+// $ ltrace ./a.out
+// +++ exited (status 0) +++
+
+#if !defined(__x86_64__) || !defined(__linux__)
+#  error This test only supports Linux __x86_64__
+#endif
+
+#include <stddef.h>
+#include <stdint.h>
+
+static void MY_exit(int exitCode);
+static void MY_abort(void);
+void *memmove(void *dst, const void *src, size_t n);
+void *memcpy(void * restrict dst, const void * restrict src, size_t n);
+void *memset(void *s, int c, size_t n);
+int memcmp(const void *s1, const void *s2, size_t n);
+
+// LZ4/HC basic freestanding setup
+#define LZ4_FREESTANDING 1
+#define LZ4_memmove(dst, src, size) memmove((dst),(src),(size))
+#define LZ4_memcpy(dst, src, size)  memcpy((dst),(src),(size))
+#define LZ4_memset(p,v,s)           memset((p),(v),(s))
+
+#include "../lib/lz4.c"
+#include "../lib/lz4hc.c"
+
+
+// Test for LZ4
+static void test_lz4(const uint8_t* srcData, int srcSize) {
+    // Compress
+    static uint8_t compressBuffer[1024 * 1024];
+    const int compressedSize = LZ4_compress_default(
+        srcData,
+        compressBuffer,
+        srcSize,
+        sizeof(compressBuffer)
+    );
+    if (compressedSize <= 0) {
+        MY_exit(__LINE__);
+    }
+
+    // Decompress
+    static uint8_t decompressBuffer[1024 * 1024];
+    const int decompressedSize = LZ4_decompress_safe(
+        compressBuffer,
+        decompressBuffer,
+        compressedSize,
+        sizeof(decompressBuffer)
+    );
+    if (decompressedSize <= 0) {
+        MY_exit(__LINE__);
+    }
+
+    // Verify
+    if (decompressedSize != srcSize) {
+        MY_exit(__LINE__);
+    }
+    if (memcmp(srcData, decompressBuffer, srcSize) != 0) {
+        MY_exit(__LINE__);
+    }
+}
+
+
+// Test for LZ4HC
+static void test_lz4hc(const uint8_t* srcData, int srcSize) {
+    // Compress
+    static uint8_t compressBuffer[1024 * 1024];
+    const int compressedSize = LZ4_compress_HC(
+        srcData,
+        compressBuffer,
+        srcSize,
+        sizeof(compressBuffer),
+        LZ4HC_CLEVEL_DEFAULT
+    );
+    if (compressedSize <= 0) {
+        MY_exit(__LINE__);
+    }
+
+    // Decompress
+    static uint8_t decompressBuffer[1024 * 1024];
+    const int decompressedSize = LZ4_decompress_safe(
+        compressBuffer,
+        decompressBuffer,
+        compressedSize,
+        sizeof(decompressBuffer)
+    );
+    if (decompressedSize <= 0) {
+        MY_exit(__LINE__);
+    }
+
+    // Verify
+    if (decompressedSize != srcSize) {
+        MY_exit(__LINE__);
+    }
+    if (memcmp(srcData, decompressBuffer, srcSize) != 0) {
+        MY_exit(__LINE__);
+    }
+}
+
+
+static void test(void) {
+    // First 256 bytes of lz4/README.md
+    static const uint8_t README_md[] = {
+        0x4c, 0x5a, 0x34, 0x20, 0x2d, 0x20, 0x45, 0x78, 0x74, 0x72, 0x65, 0x6d, 0x65, 0x6c, 0x79, 0x20,
+        0x66, 0x61, 0x73, 0x74, 0x20, 0x63, 0x6f, 0x6d, 0x70, 0x72, 0x65, 0x73, 0x73, 0x69, 0x6f, 0x6e,
+        0x0a, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d,
+        0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d, 0x3d,
+        0x3d, 0x0a, 0x0a, 0x4c, 0x5a, 0x34, 0x20, 0x69, 0x73, 0x20, 0x6c, 0x6f, 0x73, 0x73, 0x6c, 0x65,
+        0x73, 0x73, 0x20, 0x63, 0x6f, 0x6d, 0x70, 0x72, 0x65, 0x73, 0x73, 0x69, 0x6f, 0x6e, 0x20, 0x61,
+        0x6c, 0x67, 0x6f, 0x72, 0x69, 0x74, 0x68, 0x6d, 0x2c, 0x0a, 0x70, 0x72, 0x6f, 0x76, 0x69, 0x64,
+        0x69, 0x6e, 0x67, 0x20, 0x63, 0x6f, 0x6d, 0x70, 0x72, 0x65, 0x73, 0x73, 0x69, 0x6f, 0x6e, 0x20,
+        0x73, 0x70, 0x65, 0x65, 0x64, 0x20, 0x3e, 0x20, 0x35, 0x30, 0x30, 0x20, 0x4d, 0x42, 0x2f, 0x73,
+        0x20, 0x70, 0x65, 0x72, 0x20, 0x63, 0x6f, 0x72, 0x65, 0x2c, 0x0a, 0x73, 0x63, 0x61, 0x6c, 0x61,
+        0x62, 0x6c, 0x65, 0x20, 0x77, 0x69, 0x74, 0x68, 0x20, 0x6d, 0x75, 0x6c, 0x74, 0x69, 0x2d, 0x63,
+        0x6f, 0x72, 0x65, 0x73, 0x20, 0x43, 0x50, 0x55, 0x2e, 0x0a, 0x49, 0x74, 0x20, 0x66, 0x65, 0x61,
+        0x74, 0x75, 0x72, 0x65, 0x73, 0x20, 0x61, 0x6e, 0x20, 0x65, 0x78, 0x74, 0x72, 0x65, 0x6d, 0x65,
+        0x6c, 0x79, 0x20, 0x66, 0x61, 0x73, 0x74, 0x20, 0x64, 0x65, 0x63, 0x6f, 0x64, 0x65, 0x72, 0x2c,
+        0x0a, 0x77, 0x69, 0x74, 0x68, 0x20, 0x73, 0x70, 0x65, 0x65, 0x64, 0x20, 0x69, 0x6e, 0x20, 0x6d,
+        0x75, 0x6c, 0x74, 0x69, 0x70, 0x6c, 0x65, 0x20, 0x47, 0x42, 0x2f, 0x73, 0x20, 0x70, 0x65, 0x72,
+    };
+
+    static const uint8_t* srcData = README_md;
+    static const int      srcSize = (int) sizeof(README_md);
+    test_lz4  (srcData, srcSize);
+    test_lz4hc(srcData, srcSize);
+}
+
+
+// low level syscall
+#define SYS_exit (60)
+
+static __inline long os_syscall1(long n, long a1) {
+    register long rax __asm__ ("rax") = n;
+    register long rdi __asm__ ("rdi") = a1;
+    __asm__ __volatile__ ("syscall" : "+r"(rax) : "r"(rdi) : "rcx", "r11", "memory");
+    return rax;
+}
+
+static void MY_exit(int exitCode) {
+    (void) os_syscall1(SYS_exit, exitCode);
+    __builtin_unreachable();  // suppress "warning: 'noreturn' function does return"
+}
+
+static void MY_abort(void) {
+    MY_exit(-1);
+}
+
+// https://refspecs.linuxbase.org/LSB_3.0.0/LSB-Core-generic/LSB-Core-generic/baselib---assert-fail-1.html
+void __assert_fail(const char * assertion, const char * file, unsigned int line, const char * function) {
+    MY_abort();
+}
+
+
+// GCC requires memcpy, memmove, memset and memcmp.
+// https://gcc.gnu.org/onlinedocs/gcc/Standards.html
+// > GCC requires the freestanding environment provide memcpy, memmove, memset and memcmp.
+void *memmove(void *dst, const void *src, size_t n) {
+    uint8_t* d = dst;
+    const uint8_t* s = src;
+
+    if (d > s) {
+        d += n;
+        s += n;
+        while (n--) {
+            *--d = *--s;
+        }
+    } else {
+        while (n--) {
+            *d++ = *s++;
+        }
+    }
+    return dst;
+}
+
+void *memcpy(void * restrict dst, const void * restrict src, size_t n) {
+    return memmove(dst, src, n);
+}
+
+void *memset(void *s, int c, size_t n) {
+    uint8_t* p = s;
+    while (n--) {
+        *p++ = (uint8_t) c;
+    }
+    return s;
+}
+
+int memcmp(const void *s1, const void *s2, size_t n) {
+    const uint8_t* p1 = (const uint8_t*) s1;
+    const uint8_t* p2 = (const uint8_t*) s2;
+    while (n--) {
+        const uint8_t c1 = *p1++;
+        const uint8_t c2 = *p2++;
+        if (c1 < c2) {
+            return -1;
+        } else if (c1 > c2) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
+
+//
+void _start(void) {
+    test();
+    MY_exit(0);
+}
+
+int main(int argc, char** argv) {
+    test();
+    MY_exit(0);
+    return 0;
+}