# Copyright 2006 The QElectroTech Team
# This file is part of QElectroTech.
#
# QElectroTech is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# QElectroTech is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with QElectroTech. If not, see <http://www.gnu.org/licenses/>.

message(" - fetch_pugixml")

Include(FetchContent)

option(BUILD_PUGIXML "Build pugixml library, use system one otherwise" YES)

if(BUILD_PUGIXML)

  # Pinned to the commit v1.15 points at, not to the tag itself.
  #
  # A git tag is only a named pointer to a commit, and anyone with push access
  # to the upstream repository can move it (git push --force) to any other
  # commit. FetchContent fetches whatever the tag points at when the build
  # runs, so if a maintainer account or CI token is compromised, the attacker
  # can retarget a well-known release tag to malicious code: every fresh build
  # of QElectroTech then compiles it, while nothing changes in this repository
  # and the tag name still looks correct. A commit hash cannot be moved, because
  # it is derived from the content: different code always has a different hash.
  #
  # This attack has been used in the wild:
  # - March 2025, tj-actions/changed-files (CVE-2025-30066): tags v1 through
  #   v45.0.7 were retargeted to a commit that dumped CI secrets into build
  #   logs, affecting more than 23,000 repositories.
  # - March 2026, aquasecurity/trivy-action (CVE-2026-33634): 76 of 77
  #   version tags were force-pushed to a credential stealer and stayed
  #   malicious for about 12 hours.
  # Both were GitHub Actions rather than CMake dependencies, but the mechanism
  # is the same one FetchContent relies on here: resolving a git tag at build
  # time.
  #
  # To upgrade, look up the new tag's commit with git ls-remote <repo> <tag>
  # (for an annotated tag, take the hash on the "<tag>^{}" line, which is the
  # commit; the other line is the tag object), check that it is the release you
  # expect, and update both the hash and the trailing tag comment.
  FetchContent_Declare(
    pugixml
    GIT_REPOSITORY https://github.com/zeux/pugixml.git
    GIT_TAG        ee86beb30e4973f5feffe3ce63bfa4fbadf72f38) # v1.15
  set(PUGIXML_INSTALL OFF CACHE INTERNAL "")
  FetchContent_MakeAvailable(pugixml)
else()
  find_package(pugixml REQUIRED)
endif()