The go c-shared object need the libc to pass them
the argc and argv parameters in order to initialize
the runtime properly.
This is a preparation patch for this.
Since I like to be able to seemlingly prove code move
in my head this make use of a lot of class variables
that I will get rid of in next patches.
Signed-off-by: Benoît Canet <ben...@scylladb.com>
---
core/app.cc | 65 ++++++++++++++++++++++++++++--------------------------
include/osv/app.hh | 8 +++++++
2 files changed, 42 insertions(+), 31 deletions(-)
diff --git a/core/app.cc b/core/app.cc
index ad3145f..515096e 100644
--- a/core/app.cc
+++ b/core/app.cc
@@ -294,20 +294,31 @@ void application::main()
// _entry_point() doesn't return
}
-void application::run_main(std::string path, int argc, char** argv)
+void application::prepare_argc_argv()
{
- char *c_path = (char *)(path.c_str());
+ // C main wants mutable arguments, so we have can't use strings directly
+ transform(_args, back_inserter(_mut_args),
+ [](std::string s) { return std::vector<char>(s.data(), s.data() +
s.size() + 1); });
+ std::vector<char*> argv;
+ transform(_mut_args.begin(), _mut_args.end(), back_inserter(argv),
+ [](std::vector<char>& s) { return s.data(); });
+ _argc = argv.size();
+ argv.push_back(nullptr);
+
+ char **argv_data = argv.data();
+
+ char *c_path = (char *)(_command.c_str());
// path is guaranteed to keep existing this function
program_invocation_name = c_path;
program_invocation_short_name = basename(c_path);
- auto sz = argc; // for the trailing 0's.
- for (int i = 0; i < argc; ++i) {
- sz += strlen(argv[i]);
+ auto sz = _argc; // for the trailing 0's.
+ for (int i = 0; i < _argc; ++i) {
+ sz += strlen(argv_data[i]);
}
- std::unique_ptr<char []> argv_buf(new char[sz]);
- char *ab = argv_buf.get();
+ _argv_buf.reset(new char[sz]);
+ char *ab = _argv_buf.get();
// In Linux, the pointer arrays argv[] and envp[] are continguous.
// Unfortunately, some programs rely on this fact (e.g., libgo's
// runtime_goenvs_unix()) so it is useful that we do this too.
@@ -315,44 +326,36 @@ void application::run_main(std::string path, int argc,
char** argv)
while (environ[envcount]) {
envcount++;
}
- char *contig_argv[argc + 1 + envcount + 1];
+ _contig_argv.reset(new char*[_argc + 1 + envcount + 1]);
+ char **contig_argv = _contig_argv.get();
- for (int i = 0; i < argc; ++i) {
- size_t asize = strlen(argv[i]);
- memcpy(ab, argv[i], asize);
+ for (int i = 0; i < _argc; ++i) {
+ size_t asize = strlen(argv_data[i]);
+ memcpy(ab, argv_data[i], asize);
ab[asize] = '\0';
contig_argv[i] = ab;
ab += asize + 1;
}
- contig_argv[argc] = nullptr;
+ contig_argv[_argc] = nullptr;
for (int i = 0; i < envcount; i++) {
- contig_argv[argc + 1 + i] = environ[i];
+ contig_argv[_argc + 1 + i] = environ[i];
}
- contig_argv[argc + 1 + envcount] = nullptr;
-
- // make sure to have a fresh optind across calls
- // FIXME: fails if run() is executed in parallel
- int old_optind = optind;
- optind = 0;
- _return_code = _main(argc, contig_argv);
- optind = old_optind;
+ contig_argv[_argc + 1 + envcount] = nullptr;
}
void application::run_main()
{
trace_app_main(this, _command.c_str());
- // C main wants mutable arguments, so we have can't use strings directly
- std::vector<std::vector<char>> mut_args;
- transform(_args, back_inserter(mut_args),
- [](std::string s) { return std::vector<char>(s.data(), s.data() +
s.size() + 1); });
- std::vector<char*> argv;
- transform(mut_args.begin(), mut_args.end(), back_inserter(argv),
- [](std::vector<char>& s) { return s.data(); });
- auto argc = argv.size();
- argv.push_back(nullptr);
- run_main(_command, argc, argv.data());
+ prepare_argc_argv();
+
+ // make sure to have a fresh optind across calls
+ // FIXME: fails if run() is executed in parallel
+ int old_optind = optind;
+ optind = 0;
+ _return_code = _main(_argc, _contig_argv.get());
+ optind = old_optind;
if (_return_code) {
debug("program %s returned %d\n", _command.c_str(), _return_code);
diff --git a/include/osv/app.hh b/include/osv/app.hh
index 6fa503a..3ecf1a8 100644
--- a/include/osv/app.hh
+++ b/include/osv/app.hh
@@ -194,6 +194,7 @@ private:
void start_and_join(waiter* setup_waiter);
void main();
void run_main(std::string path, int argc, char** argv);
+ void prepare_argc_argv();
void run_main();
friend void ::__libc_start_main(int(*)(int, char**), int, char**,
void(*)(),
void(*)(), void(*)(), void*);
@@ -214,6 +215,13 @@ private:
void (*_entry_point)();
static app_registry apps;
+ // argc and argv variables
+ std::vector<std::vector<char>> _mut_args;
+ std::unique_ptr<char *> _contig_argv;
+ std::unique_ptr<char []> _argv_buf;
+ std::vector<char*> _argv;
+ int _argc;
+
// Must be destroyed before _lib, because contained function objects may
// have destructors which are part of the application's code.
std::list<std::function<void()>> _termination_request_callbacks;
--
2.7.4
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