semihosting tests: Add test for feature-detection

Add testing of the v2.0 feature-detection support.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 100 insertions, 0 deletions

diff --git a/semihosting.h b/semihosting.h
index 8361ffd..f8c4e7b 100644
--- a/semihosting.h
+++ b/semihosting.h
@@ -38,6 +38,12 @@
 #define REPORTEXC_REASON_APP_EXIT 0x20026
 #define SEMIHOSTING_SVC	0x123456	/* SVC comment field for semihosting */
 
+#define FEATURE_DETECT_FILE ":semihosting-features"
+#define SHFB_MAGIC_0 0x53
+#define SHFB_MAGIC_1 0x48
+#define SHFB_MAGIC_2 0x46
+#define SHFB_MAGIC_3 0x42
+
 #ifndef __ASSEMBLER__
 
 int __semi_call(int id, ...);
diff --git a/usertest.c b/usertest.c
index 6204073..de915b7 100644
--- a/usertest.c
+++ b/usertest.c
@@ -208,6 +208,96 @@ static int test_write(void)
     return 0;
 }
 
+static int test_feature_detect(void)
+{
+    int fd, fd2, remaining, len;
+
+    fd = semi_open(FEATURE_DETECT_FILE, OPEN_RDONLY);
+    if (fd == -1) {
+        semi_write0("SKIP implementation does not support feature-detection\n");
+        return 0;
+    }
+
+    /*
+     * Strictly as a semihosting client we should assume that if the
+     * magic file has less than 5 bytes or the wrong magic numbers then
+     * this indicates an implementation without feature-detection.
+     * However it's more useful for a test program to insist that they
+     * are correct.
+     */
+    len = semi_flen(fd);
+    if (len < 5) {
+        semi_write0("FAIL semihosting features file too short\n");
+        return 1;
+    }
+
+    /* Try an overlong read and check we get back something sensible */
+    remaining = semi_read(fd, filebuf, CHUNK_SZ);
+    if (remaining + len != CHUNK_SZ) {
+        semi_write0("FAIL read from semihosting features file wrong size\n");
+        return 1;
+    }
+    if (filebuf[0] != SHFB_MAGIC_0 || filebuf[1] != SHFB_MAGIC_1 ||
+        filebuf[2] != SHFB_MAGIC_2 || filebuf[3] != SHFB_MAGIC_3) {
+        semi_write0("FAIL semihosting features file has bad magic\n");
+        return 1;
+    }
+
+    semi_write0("PASS semihosting features file read successfully\n");
+
+    if (semi_istty(fd)) {
+        semi_write0("FAIL semihosting features file is a TTY?\n");
+    } else {
+        semi_write0("PASS semihosting features file is not a TTY\n");
+    }
+
+    /*
+     * Check we can open multiple fds on the magic file and that
+     * they seek independently.
+     */
+    fd2 = semi_open(FEATURE_DETECT_FILE, OPEN_RDONLY);
+    if (fd2 == -1) {
+        semi_write0("FAIL could not open feature-detection file twice\n");
+        return 1;
+    }
+
+    if (semi_seek(fd, 3) != 0) {
+        semi_write0("FAIL could not seek feature-detection file\n");
+        return 1;
+    }
+
+    if (semi_seek(fd2, 1) != 0) {
+        semi_write0("FAIL could not seek feature-detection file\n");
+        return 1;
+    }
+
+    if (semi_read(fd, filebuf, 1) != 0) {
+        semi_write0("FAIL could not read from feature-detection file\n");
+        return 1;
+    }
+
+    if (filebuf[0] != SHFB_MAGIC_3) {
+        semi_write0("FAIL feature-detection file had wrong data after seek\n");
+        return 1;
+    }
+
+    if (semi_read(fd2, filebuf, 1) != 0) {
+        semi_write0("FAIL could not read from feature-detection file\n");
+        return 1;
+    }
+
+    if (filebuf[0] != SHFB_MAGIC_1) {
+        semi_write0("FAIL feature-detection file had wrong data after seek\n");
+        return 1;
+    }
+
+    semi_write0("PASS feature-detect files seek independently\n");
+
+    semi_close(fd);
+    semi_close(fd2);
+    return 0;
+}
+
 int main(void)
 {
     void *bufp;
@@ -255,6 +345,10 @@ int main(void)
         return 1;
     }
 
+    if (test_feature_detect()) {
+        return 1;
+    }
+
     semi_write0("ALL TESTS PASSED\n");
     semi_exit(0);
     /* not reached */