Changed os_dump_core_live() to return the path to the memory dump file.

api/docs/release.dox

@@ -129,6 +129,9 @@ changes:
  - The size of #dr_mcontext_t on 32-bit Arm has been increased by 4 so that
    the struct can be pushed onto the 8-byte aligned stack without additional
    padding. The offset of the field "simd" has changed.
+ - Added new fields elf_path and elf_path_size to dr_memory_dump_spec_t. When
+   dr_create_memory_dump() returns true and elf_path is not NULL, elf_path will be
+   written with the path to the memory dump file.
 
 Further non-compatibility-affecting changes include:
  - Added support for reading a single drmemtrace trace file from stdin

core/lib/dr_tools.h

@@ -371,6 +371,16 @@ typedef struct _dr_memory_dump_spec_t {
      * in bytes, of ldmp_path.
      */
     size_t ldmp_path_size;
+    /**
+     * This field only applies to DR_MEMORY_DUMP_ELF.  This is an optional output
+     * field that, if non-NULL, will be written with the path to the created file.
+     */
+    char *elf_path;
+    /**
+     * This field only applies to DR_MEMORY_DUMP_ELF.  This is the maximum size,
+     * in bytes, of elf_path.
+     */
+    size_t elf_path_size;
 } dr_memory_dump_spec_t;
 
 DR_API

core/lib/instrument.c

@@ -2533,7 +2533,8 @@ dr_create_memory_dump(dr_memory_dump_spec_t *spec)
 #elif defined(LINUX) && \
     ((defined(X64) && defined(X86)) || (defined(AARCH64) && !defined(ANDROID64)))
     if (TEST(DR_MEMORY_DUMP_ELF, spec->flags)) {
-        return os_dump_core_live(get_thread_private_dcontext());
+        return os_dump_core_live(get_thread_private_dcontext(), spec->elf_path,
+                                 spec->elf_path_size);
     }
 #endif
     return false;

core/unix/coredump.c

@@ -380,7 +380,7 @@ write_fpregset_note(DR_PARAM_IN dcontext_t *dcontext, DR_PARAM_IN priv_mcontext_
  * false otherwise.
  */
 static bool
-os_dump_core_internal(dcontext_t *dcontext)
+os_dump_core_internal(dcontext_t *dcontext, char *path DR_PARAM_OUT, size_t path_sz)
 {
     priv_mcontext_t mc;
     if (!dr_get_mcontext_priv(dcontext, NULL, &mc))
@@ -477,6 +477,9 @@ os_dump_core_internal(dcontext_t *dcontext)
         SYSLOG_INTERNAL_ERROR("Unable to open the core dump file.");
         return false;
     }
+    if (path != NULL) {
+        d_r_strncpy(path, dump_core_file_name, path_sz);
+    }
     // We use two types of program headers. NOTE is used to store prstatus
     // structure and floating point registers. LOAD is used to specify loadable
     // segments. All but one section (shstrtab which stores section names)
@@ -650,7 +653,7 @@ os_dump_core_internal(dcontext_t *dcontext)
  * Returns true if a core dump file is written, false otherwise.
  */
 bool
-os_dump_core_live(dcontext_t *dcontext)
+os_dump_core_live(dcontext_t *dcontext, char *path DR_PARAM_OUT, size_t path_sz)
 {
 #ifdef DR_HOST_NOT_TARGET
     // Memory dump is supported only when the host and the target are the same.
@@ -671,7 +674,7 @@ os_dump_core_live(dcontext_t *dcontext)
     }
 
     // TODO i#7046: Add support to save register values for all threads.
-    const bool ret = os_dump_core_internal(dcontext);
+    const bool ret = os_dump_core_internal(dcontext, path, path_sz);
 
     end_synch_with_all_threads(threads, num_threads,
                                /*resume=*/true);

core/unix/os_exports.h

@@ -249,7 +249,7 @@ os_get_app_tls_base(dcontext_t *dcontext, reg_id_t seg);
  * mode (a process mixing 64-bit and 32-bit code) is not supported.
  */
 bool
-os_dump_core_live(dcontext_t *dcontext);
+os_dump_core_live(dcontext_t *dcontext, char *path DR_PARAM_OUT, size_t path_sz);
 #endif
 
 #if defined(AARCHXX) || defined(RISCV64)

suite/tests/client-interface/memory_dump_test.dll.c

@@ -37,10 +37,12 @@
 #endif
 
 #define NUDGE_ARG_DUMP_MEMORY 1
+#define MAX_PATH_SIZE 200
 
 static bool saw_thread_init_event = false;
 static client_id_t client_id = 0;
 static thread_id_t thread_id = 0;
+static char path[MAX_PATH_SIZE];
 
 static void
 event_nudge(void *drcontext, uint64 arg)
@@ -53,9 +55,33 @@ event_nudge(void *drcontext, uint64 arg)
         spec.flags = DR_MEMORY_DUMP_LDMP;
 #else
         spec.flags = DR_MEMORY_DUMP_ELF;
+        spec.elf_path = (char *)&path;
+        spec.elf_path_size = MAX_PATH_SIZE;
 #endif
-        if (!dr_create_memory_dump(&spec))
+        if (!dr_create_memory_dump(&spec)) {
             dr_fprintf(STDERR, "Error: failed to create memory dump.\n");
+            return;
+        }
+
+        file_t memory_dump_file = dr_open_file(path, DR_FILE_READ);
+        if (memory_dump_file < 0) {
+            dr_fprintf(STDERR, "Error: failed to read memory dump file: %s.\n", path);
+            return;
+        }
+
+        uint64 file_size;
+        if (!dr_file_size(memory_dump_file, &file_size)) {
+            dr_fprintf(STDERR,
+                       "Error: failed to read the size of the memory dump file: %s.\n",
+                       path);
+            dr_close_file(memory_dump_file);
+            return;
+        }
+
+        if (file_size == 0)
+            dr_fprintf(STDERR, "Error: memory dump file %s is empty.\n", path);
+
+        dr_close_file(memory_dump_file);
         return;
     }
     dr_fprintf(STDERR, "Error: unexpected nudge event!\n");