MacOS development: add a setting to override virtiofs paths

include/dso_hdr.hpp

@@ -8,7 +8,9 @@
 #include <array>
 #include <cassert>
 #include <map>
+#include <optional>
 #include <string>
+#include <string_view>
 #include <unordered_map>
 #include <unordered_set>
 
@@ -216,6 +218,9 @@ class DsoHdr {
   FileInfoId_t update_id_dd_profiling(const Dso &dso);
 
   FileInfoId_t update_id_from_path(const Dso &dso);
+  std::optional<std::string>
+  remap_host_workspace_path(std::string_view original) const;
+  void init_workspace_remap();
 
   // Unordered map (by pid) of sorted DSOs
   DsoPidMap _pid_map;
@@ -224,6 +229,8 @@ class DsoHdr {
   FileInfoVector _file_info_vector;
   std::string _path_to_proc; // /proc files can be mounted at various places
                              // (whole host profiling)
+  std::string _workspace_host_prefix;
+  std::string _workspace_container_root;
   int _dd_profiling_fd;
   // Assumption is that we have a single version of the dd_profiling library
   // across all PIDs.

src/dso_hdr.cc

@@ -16,6 +16,7 @@
 
 #include <algorithm>
 #include <cassert>
+#include <cstdlib>
 #include <cstring>
 #include <fcntl.h>
 #include <memory>
@@ -109,6 +110,7 @@ DsoHdr::DsoHdr(std::string_view path_to_proc, int dd_profiling_fd)
   } else {
     _path_to_proc = path_to_proc;
   }
+  init_workspace_remap();
   // 0 element is error element
   _file_info_vector.emplace_back(FileInfo(), 0);
 }
@@ -528,6 +530,57 @@ Dso DsoHdr::dso_from_proc_line(int pid, const char *line) {
           DsoOrigin::kProcMaps};
 }
 
+void DsoHdr::init_workspace_remap() {
+  _workspace_host_prefix.clear();
+  _workspace_container_root.clear();
+  if (const char *workspace_env = std::getenv("DDPROF_WORKSPACE_ROOT");
+      workspace_env && workspace_env[0] != '\0') {
+    const std::string mapping = workspace_env;
+    auto const sep = mapping.find('|');
+    if (sep != std::string::npos) {
+      _workspace_host_prefix = mapping.substr(0, sep);
+      _workspace_container_root = mapping.substr(sep + 1);
+    } else {
+      LG_WRN("DDPROF_WORKSPACE_ROOT is expected to be "
+             "'<host_prefix>|<container_root>'");
+    }
+  }
+  auto trim_trailing_slash = [](std::string &path) {
+    while (path.size() > 1 && path.back() == '/') {
+      path.pop_back();
+    }
+  };
+  trim_trailing_slash(_workspace_host_prefix);
+  trim_trailing_slash(_workspace_container_root);
+  if (_workspace_host_prefix.empty() || _workspace_container_root.empty()) {
+    _workspace_host_prefix.clear();
+    _workspace_container_root.clear();
+  } else {
+    LG_NTC("DDPROF_WORKSPACE_ROOT is set to %s|%s",
+           _workspace_host_prefix.c_str(), _workspace_container_root.c_str());
+  }
+}
+
+// On macOS with Docker / virtiofs, /proc/pid/maps exposes host-backed paths
+// (e.g. /run/host_virtiofs/Users/foo/ddprof/build/...) instead of the
+// in-container path (/app/build/...).  When DDPROF_WORKSPACE_ROOT is set,
+// strip the host prefix and replace it with the container root so that
+// libdwfl can locate the ELF file.
+std::optional<std::string>
+DsoHdr::remap_host_workspace_path(std::string_view original) const {
+  if (_workspace_host_prefix.empty()) {
+    return std::nullopt;
+  }
+  if (!original.starts_with(_workspace_host_prefix)) {
+    return std::nullopt;
+  }
+  auto suffix = original.substr(_workspace_host_prefix.size());
+  if (!suffix.empty() && suffix[0] != '/') {
+    return std::nullopt;
+  }
+  return _workspace_container_root + std::string(suffix);
+}
+
 FileInfo DsoHdr::find_file_info(const Dso &dso) {
   int64_t size;
   inode_t inode;
@@ -551,6 +604,14 @@ FileInfo DsoHdr::find_file_info(const Dso &dso) {
     return {proc_path, size, inode};
   }
 
+  if (auto remapped = remap_host_workspace_path(dso._filename)) {
+    if (get_file_inode(remapped->c_str(), &inode, &size)) {
+      LG_DBG("[DSO] Remapped %s -> %s", dso._filename.c_str(),
+             remapped->c_str());
+      return {*remapped, size, inode};
+    }
+  }
+
   LG_DBG("[DSO] Unable to find path to %s", dso._filename.c_str());
   return {};
 }

test/ddprof_stats-ut.cc

@@ -81,7 +81,7 @@ TEST(ddprof_statsTest, ConnectAndSet) {
 }
 
 TEST(ddprof_statsTest, Arithmetic) {
-  const char path_listen[] = UNIT_TEST_DATA "/my_statsd_listener.sock";
+  const char path_listen[] = "/tmp/my_statsd_listener_arithmetic";
   unlink(path_listen); // make sure node is available, OK if this fails
 
   // Initiate "server"

test/dso-ut.cc

@@ -5,10 +5,15 @@
 
 #include "dso_hdr.hpp"
 
+#include <cstdlib>
+#include <filesystem>
+#include <fstream>
 #include <gtest/gtest.h>
 #include <pthread.h>
 #include <string>
 #include <sys/mman.h>
+#include <unistd.h>
+#include <vector>
 
 #include "defer.hpp"
 #include "loghandle.hpp"
@@ -393,6 +398,40 @@ TEST(DSOTest, missing_dso) {
   EXPECT_FALSE(file_info._inode);
 }
 
+TEST(DSOTest, WorkspaceRemapping) {
+  std::string base_template =
+      std::filesystem::temp_directory_path() / "ddprof-workspace-remapXXXXXX";
+  std::vector<char> tmpl(base_template.begin(), base_template.end());
+  tmpl.push_back('\0');
+  char *tmp_dir = mkdtemp(tmpl.data());
+  ASSERT_NE(tmp_dir, nullptr);
+  auto cleanup_dir =
+      make_defer([&]() { std::filesystem::remove_all(tmp_dir); });
+
+  std::string container_root = tmp_dir;
+  std::string relative_path = "/subdir/test_binary";
+  std::filesystem::create_directories(container_root + "/subdir");
+
+  std::string container_file = container_root + relative_path;
+  {
+    std::ofstream ofs(container_file);
+    ofs << "test";
+  }
+
+  std::string host_prefix = "/run/host_virtiofs/Users/test/ddprof";
+  std::string host_path = host_prefix + relative_path;
+  std::string env_value = host_prefix + "|" + container_root;
+  setenv("DDPROF_WORKSPACE_ROOT", env_value.c_str(), 1);
+  auto cleanup_env = make_defer([]() { unsetenv("DDPROF_WORKSPACE_ROOT"); });
+
+  DsoHdr dso_hdr;
+  Dso remap_dso(getpid(), 0x1000, 0x2000, 0, std::move(host_path));
+  FileInfo file_info = dso_hdr.find_file_info(remap_dso);
+
+  EXPECT_EQ(file_info._path, container_file);
+  EXPECT_NE(file_info._inode, 0);
+}
+
 // clang-format off
 // Assuming we get a big insertion
 // <DEBUG>Dec 14 14:15:16 ddprof[725]: <0>(MAP)722: /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.25 (7f51f1d42000/389000/0)

tools/launch_local_build.sh

@@ -88,6 +88,15 @@ if [ -e "${CURRENTDIR}/.env" ]; then
 fi
 
 MOUNT_CMD="-v ${DEFAULT_DEV_WORKSPACE:-${CURRENTDIR}}:/app"
+# avoid symlinks
+HOST_SHARE_PATH=$(python3 - <<'PY'
+import os, sys
+path = os.environ.get("DEFAULT_DEV_WORKSPACE", os.environ.get("CURRENTDIR"))
+if not path:
+    path = os.getcwd()
+print(os.path.realpath(path), end="")
+PY
+)
 
 # Support docker sync : Improves compilation speed 
 # Example of config (to be pasted in the docker-sync.yml file)
@@ -102,6 +111,7 @@ if [ -e "${CURRENTDIR}/docker-sync.yml" ]; then
     VOLUME_SYNC=$(grep -A 1 "syncs:" "${CURRENTDIR}/docker-sync.yml" | tail -n 1 | awk -F ':' '{print $1}' | sed "s/ //g")
     echo "$VOLUME_SYNC"
     MOUNT_CMD="--mount source=${VOLUME_SYNC},target=/app"
+    HOST_SHARE_PATH=""
     if ! docker-sync list | grep -q "$VOLUME_SYNC"; then
         echo "Please generate a volume: $VOLUME_SYNC"
         echo "Suggested commands:"
@@ -130,13 +140,15 @@ if [ $PERFORM_CLEAN -eq 1 ]; then
 fi
 
 # Check if base image exists
-if [ ! ${CUSTOM_ID:-,,} == "yes" ] && ! docker images | awk '{print $1}'| grep -qE "^${DOCKER_NAME}$"; then
-    echo "Building image"
-    BUILD_CMD="docker build $CACHE_OPTION -t ${DOCKER_NAME} --build-arg COMPILER=$COMPILER --build-arg UBUNTU_VERSION=${UBUNTU_VERSION} -f $BASE_DOCKERFILE ."
-    #echo "${BUILD_CMD}"
-    eval "${BUILD_CMD}"
-else 
-    echo "Base image found, not rebuilding. Remove it to force rebuild."
+if [ ! ${CUSTOM_ID:-,,} == "yes" ]; then
+    if ! docker image inspect "${DOCKER_NAME}" >/dev/null 2>&1; then
+        echo "Building image"
+        BUILD_CMD="docker build $CACHE_OPTION -t ${DOCKER_NAME} --build-arg COMPILER=$COMPILER --build-arg UBUNTU_VERSION=${UBUNTU_VERSION} -f $BASE_DOCKERFILE ."
+        #echo "${BUILD_CMD}"
+        eval "${BUILD_CMD}"
+    else 
+        echo "Base image found, not rebuilding. Remove it to force rebuild."
+    fi
 fi
 
 if [[ $OSTYPE == darwin* ]]; then
@@ -162,6 +174,15 @@ else
   MOUNT_TOOLS_DIR=""
 fi
 
-CMD="docker run -it --rm -u $(id -u):$(id -g) --network=host -w /app ${MOUNT_SSH_AGENT} ${MOUNT_TOOLS_DIR} --cap-add CAP_SYS_PTRACE --cap-add SYS_ADMIN ${MOUNT_CMD} \"${DOCKER_NAME}${DOCKER_TAG}\" /bin/bash"
+WORKSPACE_ENV=""
+if [[ $OSTYPE == darwin* ]] && [ -n "${HOST_SHARE_PATH}" ]; then
+  HOST_PREFIX="/run/host_virtiofs${HOST_SHARE_PATH}"
+  CONTAINER_ROOT="/app"
+  WORKSPACE_ENV="-e DDPROF_WORKSPACE_ROOT=${HOST_PREFIX}|${CONTAINER_ROOT}"
+fi
 
-eval "$CMD"
+# shellcheck disable=SC2086
+docker run -it --rm -u "$(id -u):$(id -g)" --network=host -w /app \
+  ${MOUNT_SSH_AGENT} ${MOUNT_TOOLS_DIR} ${WORKSPACE_ENV} \
+  --cap-add CAP_SYS_PTRACE --cap-add SYS_ADMIN ${MOUNT_CMD} \
+  "${DOCKER_NAME}${DOCKER_TAG}" /bin/bash