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#include "config_overrides.hpp"
#ifdef EMSCRIPTEN
# include
# include
# include "git_exception.hpp"
#endif
void apply_config_overrides([[maybe_unused]] git_repository* repo)
{
#ifdef EMSCRIPTEN
// Config values to override, each in "name=value" form. core.filemode is disabled because
// the emscripten filesystem does support executable file permissions but some JupyterLite
// drive implementations do not.
const char* values[] = {"core.filemode=false"};
// Create an in-memory config backend holding these values. This backend is read-only, so
// any config writes (e.g. `git config` or values set by clone/init) skip it and go to the
// highest-priority writable backend instead, which is the repository's own config file.
// The overrides are therefore never persisted to disk. backend_type is a label that
// identifies where these entries came from when inspecting a config entry's origin.
git_config_backend* backend = nullptr;
git_config_backend_memory_options opts = GIT_CONFIG_BACKEND_MEMORY_OPTIONS_INIT;
opts.backend_type = "git2cpp-overrides";
throw_if_error(git_config_backend_from_values(&backend, values, std::size(values), &opts));
// git_repository_config returns the repository's cached, shared config object rather than a
// copy, so adding a backend to it affects all later config lookups through this repository.
// GIT_CONFIG_LEVEL_APP is the highest priority level, above the local, global and system
// config files, so these values win over any existing setting. The repo is passed so that
// conditional includes can be evaluated, and force=0 means fail rather than replace if a
// backend already exists at this level.
git_config* cfg = nullptr;
int error = git_repository_config(&cfg, repo);
if (error == 0)
{
error = git_config_add_backend(cfg, backend, GIT_CONFIG_LEVEL_APP, repo, 0);
// Only releases our reference; the repository still holds the config and its backends.
git_config_free(cfg);
}
if (error < 0)
{
// On success ownership of the backend passes to the config, but on failure it is still
// ours to free.
backend->free(backend);
throw_if_error(error);
}
#endif
}