[PATCH 1/4] fuzz: add datadir for oss-fuzz compatability

[Alexander Bulekov <alxndr@bu.edu>]

This allows us to keep pc-bios in executable_dir/pc-bios, rather than
executable_dir/../pc-bios, which is incompatible with oss-fuzz' file
structure.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
---
 include/sysemu/sysemu.h |  2 ++
 softmmu/vl.c            |  2 +-
 tests/qtest/fuzz/fuzz.c | 15 +++++++++++++++
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
index ef81302e1a..cc96b66fc9 100644
--- a/include/sysemu/sysemu.h
+++ b/include/sysemu/sysemu.h
@@ -15,6 +15,8 @@ extern const char *qemu_name;
 extern QemuUUID qemu_uuid;
 extern bool qemu_uuid_set;
 
+void qemu_add_data_dir(const char *path);
+
 void qemu_add_exit_notifier(Notifier *notify);
 void qemu_remove_exit_notifier(Notifier *notify);
 
diff --git a/softmmu/vl.c b/softmmu/vl.c
index afd2615fb3..c71485a965 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -1993,7 +1993,7 @@ char *qemu_find_file(int type, const char *name)
     return NULL;
 }
 
-static void qemu_add_data_dir(const char *path)
+void qemu_add_data_dir(const char *path)
 {
     int i;
 
diff --git a/tests/qtest/fuzz/fuzz.c b/tests/qtest/fuzz/fuzz.c
index f5c923852e..33365c3782 100644
--- a/tests/qtest/fuzz/fuzz.c
+++ b/tests/qtest/fuzz/fuzz.c
@@ -137,6 +137,7 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, char ***envp)
 {
 
     char *target_name;
+    char *dir;
 
     /* Initialize qgraph and modules */
     qos_graph_init();
@@ -147,6 +148,20 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, char ***envp)
     target_name = strstr(**argv, "-target-");
     if (target_name) {        /* The binary name specifies the target */
         target_name += strlen("-target-");
+        /*
+         * With oss-fuzz, the executable is kept in the root of a directory (we
+         * cannot assume the path). All data (including bios binaries) must be
+         * in the same dir, or a subdir. Thus, we cannot place the pc-bios so
+         * that it would be in exec_dir/../pc-bios.
+         * As a workaround, oss-fuzz allows us to use argv[0] to get the
+         * location of the executable. Using this we add exec_dir/pc-bios to
+         * the datadirs.
+         */
+        dir = g_build_filename(g_path_get_dirname(**argv), "pc-bios", NULL);
+        if (g_file_test(dir, G_FILE_TEST_IS_DIR)) {
+            qemu_add_data_dir(dir);
+        }
+        g_free(dir);
     } else if (*argc > 1) {  /* The target is specified as an argument */
         target_name = (*argv)[1];
         if (!strstr(target_name, "--fuzz-target=")) {
-- 
2.26.2