[RFC,v4,10/11] tests/tcg/multiarch: Add nativecall.c test

Introduce a new test for native calls to ensure their functionality.
The process involves cross-compiling the test cases, building them
as dynamically linked binaries, and running these binaries which
necessitates the addition of the appropriate interpreter prefix.

Signed-off-by: Yeqi Fu <fufuyqqqqqq@gmail.com>
---
 tests/tcg/multiarch/Makefile.target     | 17 +++++
 tests/tcg/multiarch/native/nativecall.c | 98 +++++++++++++++++++++++++
 2 files changed, 115 insertions(+)
 create mode 100644 tests/tcg/multiarch/native/nativecall.c

Yeqi Fu <fufuyqqqqqq@gmail.com> writes:

> Introduce a new test for native calls to ensure their functionality.
> The process involves cross-compiling the test cases, building them
> as dynamically linked binaries, and running these binaries which
> necessitates the addition of the appropriate interpreter prefix.
>
> Signed-off-by: Yeqi Fu <fufuyqqqqqq@gmail.com>
> ---
>  tests/tcg/multiarch/Makefile.target     | 17 +++++
>  tests/tcg/multiarch/native/nativecall.c | 98 +++++++++++++++++++++++++
>  2 files changed, 115 insertions(+)
>  create mode 100644 tests/tcg/multiarch/native/nativecall.c
>
> diff --git a/tests/tcg/multiarch/Makefile.target b/tests/tcg/multiarch/Makefile.target
> index 43bddeaf21..5231df34ba 100644
> --- a/tests/tcg/multiarch/Makefile.target
> +++ b/tests/tcg/multiarch/Makefile.target
> @@ -138,5 +138,22 @@ run-plugin-semiconsole-with-%:
>  TESTS += semihosting semiconsole
>  endif
>  
> +nativecall: native/nativecall.c
> +	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
> +
> +ifneq ($(LD_PREFIX),)
> +ifneq ($(wildcard $(LIBNATIVE)),)
> +run-nativecall: nativecall
> +	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass $(LIBNATIVE) $<, "nativecall")
> +else
> +run-nativecall: nativecall
> +	$(call skip-test, $<, "no native library found")
> +endif
> +else
> +run-nativecall: nativecall
> +	$(call skip-test, $<, "no elf interpreter prefix found")
> +endif
> +EXTRA_RUNS += run-nativecall
> +
>  # Update TESTS
>  TESTS += $(MULTIARCH_TESTS)
> diff --git a/tests/tcg/multiarch/native/nativecall.c b/tests/tcg/multiarch/native/nativecall.c
> new file mode 100644
> index 0000000000..d3f6f49ed0
> --- /dev/null
> +++ b/tests/tcg/multiarch/native/nativecall.c
> @@ -0,0 +1,98 @@
> +#include <assert.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <sys/mman.h>
> +
> +void compare_memory(const void *a, const void *b, size_t n)
> +{
> +    const unsigned char *p1 = a;
> +    const unsigned char *p2 = b;
> +    for (size_t i = 0; i < n; i++) {
> +        assert(p1[i] == p2[i]);
> +    }
> +}
> +
> +void test_memcpy()
> +{
> +    char src[] = "Hello, world!";
> +    char dest[20];
> +    memcpy(dest, src, 13);
> +    compare_memory(dest, src, 13);
> +}

As discussed earlier expanding the range of sizes involved will help get
more coverage especially as routines are usually optimised to handle
various alignments and block sizes.

You can also use a --enable-gcov build and check how much coverage of
your new code is hit by the test cases.

> +
> +void test_strncpy()
> +{
> +    char src[] = "Hello, world!";
> +    char dest[20];
> +    strncpy(dest, src, 13);
> +    compare_memory(dest, src, 13);
> +}
> +
> +void test_strcpy()
> +{
> +    char src[] = "Hello, world!";
> +    char dest[20];
> +    strcpy(dest, src);
> +    compare_memory(dest, src, 13);
> +}
> +
> +void test_strcat()
> +{
> +    char src[20] = "Hello, ";
> +    char dst[] = "world!";
> +    char str[] = "Hello, world!";
> +    strcat(src, dest);

copy and paste fail here (dst/dest) means it doesn't compile.

It's always good practice to make sure your tree passes a make check (or
at least check-tcg in the user-mode case) to ensure no silly bugs are
present.

You can also create a gitlab account and take advantage of the CI. See
this run for example:

  https://gitlab.com/stsquad/qemu/-/pipelines/959899240/failures

> +    compare_memory(src, str, 13);
> +}
> +
> +void test_memcmp()
> +{
> +    char str1[] = "abc";
> +    char str2[] = "abc";
> +    char str3[] = "def";
> +    assert(memcmp(str1, str2, 3) == 0);
> +    assert(memcmp(str1, str3, 3) != 0);
> +}
> +
> +void test_strncmp()
> +{
> +    char str1[] = "abc";
> +    char str2[] = "abc";
> +    char str3[] = "def";
> +    assert(strncmp(str1, str2, 2) == 0);
> +    assert(strncmp(str1, str3, 2) != 0);
> +}
> +
> +void test_strcmp()
> +{
> +    char str1[] = "abc";
> +    char str2[] = "abc";
> +    char str3[] = "def";
> +    assert(strcmp(str1, str2) == 0);
> +    assert(strcmp(str1, str3) != 0);
> +}
> +
> +void test_memset()
> +{
> +    char buffer[10];
> +    memset(buffer, 'A', 10);
> +    int i;
> +    for (i = 0; i < 10; i++) {
> +        assert(buffer[i] == 'A');
> +    }
> +}
> +
> +int main()
> +{
> +    test_memset();
> +    test_memcpy();
> +    test_strncpy();
> +    test_memcmp();
> +    test_strncmp();
> +    test_strcpy();
> +    test_strcmp();
> +    test_strcat();
> +
> +    return EXIT_SUCCESS;
> +}

Yeqi Fu <fufuyqqqqqq@gmail.com> writes:

> Introduce a new test for native calls to ensure their functionality.
> The process involves cross-compiling the test cases, building them
> as dynamically linked binaries, and running these binaries which
> necessitates the addition of the appropriate interpreter prefix.
>
> Signed-off-by: Yeqi Fu <fufuyqqqqqq@gmail.com>
> ---
>  tests/tcg/multiarch/Makefile.target     | 17 +++++
>  tests/tcg/multiarch/native/nativecall.c | 98
> +++++++++++++++++++++++++

Another thing I missed is putting the test in a subdir misses out the
common logic:

  # Set search path for all sources
  VPATH 	       += $(MULTIARCH_SRC)
  MULTIARCH_SRCS =  $(notdir $(wildcard $(MULTIARCH_SRC)/*.c))
  ifeq ($(filter %-linux-user, $(TARGET)),$(TARGET))
  VPATH 	       += $(MULTIARCH_SRC)/linux
  MULTIARCH_SRCS += $(notdir $(wildcard $(MULTIARCH_SRC)/linux/*.c))
  endif
  MULTIARCH_TESTS = $(MULTIARCH_SRCS:.c=)

which as a result means things like:

  make build-tcg

don't automatically build the tests (although it does get picked up at
runtime).

You can either move it out of the subdir or do something similar that
the arm-compat-semi does, expand VPATH and use TESTS:

modified   tests/tcg/multiarch/Makefile.target
@@ -138,13 +138,18 @@ run-plugin-semiconsole-with-%:
 TESTS += semihosting semiconsole
 endif
 
-nativecall: native/nativecall.c
-	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
-
 ifneq ($(LD_PREFIX),)
 ifneq ($(wildcard $(LIBNATIVE)),)
+VPATH += $(MULTIARCH_SRC)/native
+
+nativecall: nativecall.c
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
+
 run-nativecall: nativecall
-	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass $(LIBNATIVE) $<, "nativecall")
+	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass
+	$(LIBNATIVE) $<, "nativecall")
+
+TESTS += nativecall
 else
 run-nativecall: nativecall
 	$(call skip-test, $<, "no native library found")
@@ -153,7 +158,6 @@ else
 run-nativecall: nativecall
 	$(call skip-test, $<, "no elf interpreter prefix found")
 endif
-EXTRA_RUNS += run-nativecall


>  2 files changed, 115 insertions(+)
>  create mode 100644 tests/tcg/multiarch/native/nativecall.c
>
> diff --git a/tests/tcg/multiarch/Makefile.target b/tests/tcg/multiarch/Makefile.target
> index 43bddeaf21..5231df34ba 100644
> --- a/tests/tcg/multiarch/Makefile.target
> +++ b/tests/tcg/multiarch/Makefile.target
> @@ -138,5 +138,22 @@ run-plugin-semiconsole-with-%:
>  TESTS += semihosting semiconsole
>  endif
>  
> +nativecall: native/nativecall.c
> +	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
> +
> +ifneq ($(LD_PREFIX),)
> +ifneq ($(wildcard $(LIBNATIVE)),)
> +run-nativecall: nativecall
> +	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass $(LIBNATIVE) $<, "nativecall")
> +else
> +run-nativecall: nativecall
> +	$(call skip-test, $<, "no native library found")
> +endif
> +else
> +run-nativecall: nativecall
> +	$(call skip-test, $<, "no elf interpreter prefix found")
> +endif
> +EXTRA_RUNS += run-nativecall
> +
>  # Update TESTS
>  TESTS += $(MULTIARCH_TESTS)
> diff --git a/tests/tcg/multiarch/native/nativecall.c b/tests/tcg/multiarch/native/nativecall.c
> new file mode 100644
> index 0000000000..d3f6f49ed0
> --- /dev/null
> +++ b/tests/tcg/multiarch/native/nativecall.c
> @@ -0,0 +1,98 @@
> +#include <assert.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <sys/mman.h>
> +
> +void compare_memory(const void *a, const void *b, size_t n)
> +{
> +    const unsigned char *p1 = a;
> +    const unsigned char *p2 = b;
> +    for (size_t i = 0; i < n; i++) {
> +        assert(p1[i] == p2[i]);
> +    }
> +}
> +
> +void test_memcpy()
> +{
> +    char src[] = "Hello, world!";
> +    char dest[20];
> +    memcpy(dest, src, 13);
> +    compare_memory(dest, src, 13);
> +}
> +
> +void test_strncpy()
> +{
> +    char src[] = "Hello, world!";
> +    char dest[20];
> +    strncpy(dest, src, 13);
> +    compare_memory(dest, src, 13);
> +}
> +
> +void test_strcpy()
> +{
> +    char src[] = "Hello, world!";
> +    char dest[20];
> +    strcpy(dest, src);
> +    compare_memory(dest, src, 13);
> +}
> +
> +void test_strcat()
> +{
> +    char src[20] = "Hello, ";
> +    char dst[] = "world!";
> +    char str[] = "Hello, world!";
> +    strcat(src, dest);
> +    compare_memory(src, str, 13);
> +}
> +
> +void test_memcmp()
> +{
> +    char str1[] = "abc";
> +    char str2[] = "abc";
> +    char str3[] = "def";
> +    assert(memcmp(str1, str2, 3) == 0);
> +    assert(memcmp(str1, str3, 3) != 0);
> +}
> +
> +void test_strncmp()
> +{
> +    char str1[] = "abc";
> +    char str2[] = "abc";
> +    char str3[] = "def";
> +    assert(strncmp(str1, str2, 2) == 0);
> +    assert(strncmp(str1, str3, 2) != 0);
> +}
> +
> +void test_strcmp()
> +{
> +    char str1[] = "abc";
> +    char str2[] = "abc";
> +    char str3[] = "def";
> +    assert(strcmp(str1, str2) == 0);
> +    assert(strcmp(str1, str3) != 0);
> +}
> +
> +void test_memset()
> +{
> +    char buffer[10];
> +    memset(buffer, 'A', 10);
> +    int i;
> +    for (i = 0; i < 10; i++) {
> +        assert(buffer[i] == 'A');
> +    }
> +}
> +
> +int main()
> +{
> +    test_memset();
> +    test_memcpy();
> +    test_strncpy();
> +    test_memcmp();
> +    test_strncmp();
> +    test_strcpy();
> +    test_strcmp();
> +    test_strcat();
> +
> +    return EXIT_SUCCESS;
> +}

Yeqi Fu <fufuyqqqqqq@gmail.com> writes:

> Introduce a new test for native calls to ensure their functionality.
> The process involves cross-compiling the test cases, building them
> as dynamically linked binaries, and running these binaries which
> necessitates the addition of the appropriate interpreter prefix.
>
> Signed-off-by: Yeqi Fu <fufuyqqqqqq@gmail.com>
> ---
>  tests/tcg/multiarch/Makefile.target     | 17 +++++
>  tests/tcg/multiarch/native/nativecall.c | 98 +++++++++++++++++++++++++
>  2 files changed, 115 insertions(+)
>  create mode 100644 tests/tcg/multiarch/native/nativecall.c
>
> diff --git a/tests/tcg/multiarch/Makefile.target b/tests/tcg/multiarch/Makefile.target
> index 43bddeaf21..5231df34ba 100644
> --- a/tests/tcg/multiarch/Makefile.target
> +++ b/tests/tcg/multiarch/Makefile.target
> @@ -138,5 +138,22 @@ run-plugin-semiconsole-with-%:
>  TESTS += semihosting semiconsole
>  endif
>  
> +nativecall: native/nativecall.c
> +	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
> +
> +ifneq ($(LD_PREFIX),)
> +ifneq ($(wildcard $(LIBNATIVE)),)
> +run-nativecall: nativecall
> +	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass $(LIBNATIVE) $<, "nativecall")
> +else
> +run-nativecall: nativecall
> +	$(call skip-test, $<, "no native library found")
> +endif
> +else
> +run-nativecall: nativecall
> +	$(call skip-test, $<, "no elf interpreter prefix found")
> +endif
> +EXTRA_RUNS += run-nativecall
> +

Or indeed just expand VPATH and use TESTS instead of EXTRA_RUNS (which
is for additional configurations of tests):

modified   tests/tcg/multiarch/Makefile.target
@@ -138,13 +138,18 @@ run-plugin-semiconsole-with-%:
 TESTS += semihosting semiconsole
 endif
 
-nativecall: native/nativecall.c
-	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
-
 ifneq ($(LD_PREFIX),)
 ifneq ($(wildcard $(LIBNATIVE)),)
+VPATH += $(MULTIARCH_SRC)/native
+
+nativecall: nativecall.c
+	$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(filter-out -static,$(LDFLAGS))
+
 run-nativecall: nativecall
-	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass $(LIBNATIVE) $<, "nativecall")
+	$(call run-test,$<, $(QEMU) -L $(LD_PREFIX) --native-bypass
+	$(LIBNATIVE) $<, "nativecall")
+
+TESTS += nativecall
 else
 run-nativecall: nativecall
 	$(call skip-test, $<, "no native library found")
@@ -153,7 +158,6 @@ else
 run-nativecall: nativecall
 	$(call skip-test, $<, "no elf interpreter prefix found")
 endif
-EXTRA_RUNS += run-nativecall