Replace our custom home-made XML parser with pugixml

[lemenkov]

Replace custom XML parser with pugixml

Replace the hand-rolled xp_parser with pugixml, a well-tested and widely-used XML parsing library.

Benefits

• Removes hardcoded limits: No more 64KB file size limit (XP_MAX_FILE_LEN) or 256-level nesting limit (XP_MAX_STACK_LEN)
• Better XML compliance: Proper handling of edge cases, entities, and malformed input
• Improved error reporting: Accurate line numbers for parse errors
• Maintained library: Benefits from upstream bug fixes and security updates
• Smaller codebase: Net reduction of ~330 lines
• Battle-tested: pugixml is used by thousands of projects

Approach

The existing xp_... API is preserved, so callers remain unchanged. This minimizes risk and allows gradual migration to direct pugixml usage in the future if desired.

Dependencies

pugixml is bundled by default as a git submodule — no new external dependencies required. Distributions can use -DUSE_SYSTEM_PUGIXML=ON to link against system-installed pugixml instead.

Building

git clone --recursive https://github.com/SIPp/sipp.git
# or for existing clones:
git submodule update --init

[orgads]

Is it really needed as a submodule?