rust/src/rt/rust_env.cpp
2011-07-28 12:53:14 -07:00

119 lines
2.7 KiB
C++

// The runtime wants to pull a number of variables out of the
// environment but calling getenv is not threadsafe, so every value
// that might come from the environment is loaded here, once, during
// init.
#include "rust_internal.h"
// The environment variables that the runtime knows about
#define RUST_THREADS "RUST_THREADS"
#define RUST_MIN_STACK "RUST_MIN_STACK"
#define RUST_LOG "RUST_LOG"
#define CHECK_CLAIMS "CHECK_CLAIMS"
#define DETAILED_LEAKS "DETAILED_LEAKS"
#define RUST_SEED "RUST_SEED"
#if defined(__WIN32__)
static int
get_num_cpus() {
SYSTEM_INFO sysinfo;
GetSystemInfo(&sysinfo);
return (int) sysinfo.dwNumberOfProcessors;
}
#elif defined(__BSD__)
static int
get_num_cpus() {
/* swiped from http://stackoverflow.com/questions/150355/
programmatically-find-the-number-of-cores-on-a-machine */
unsigned int numCPU;
int mib[4];
size_t len = sizeof(numCPU);
/* set the mib for hw.ncpu */
mib[0] = CTL_HW;
mib[1] = HW_AVAILCPU; // alternatively, try HW_NCPU;
/* get the number of CPUs from the system */
sysctl(mib, 2, &numCPU, &len, NULL, 0);
if( numCPU < 1 ) {
mib[1] = HW_NCPU;
sysctl( mib, 2, &numCPU, &len, NULL, 0 );
if( numCPU < 1 ) {
numCPU = 1;
}
}
return numCPU;
}
#elif defined(__GNUC__)
static int
get_num_cpus() {
return sysconf(_SC_NPROCESSORS_ONLN);
}
#endif
static int
get_num_threads()
{
char *env = getenv(RUST_THREADS);
if(env) {
int num = atoi(env);
if(num > 0)
return num;
}
return get_num_cpus();
}
// FIXME (issue #151): This should be 0x300; the change here is for
// practicality's sake until stack growth is working.
static size_t
get_min_stk_size() {
char *stack_size = getenv(RUST_MIN_STACK);
if(stack_size) {
return strtol(stack_size, NULL, 0);
}
else {
return 0x300000;
}
}
static char*
copyenv(const char* name) {
char *envvar = getenv(name);
if (!envvar) {
return NULL;
} else {
size_t slen = strlen(envvar);
size_t buflen = slen + 1;
char *var = (char*)malloc(buflen);
memset(var, 0, buflen);
strncpy(var, envvar, slen);
return var;
}
}
rust_env*
load_env() {
rust_env *env = (rust_env*)malloc(sizeof(rust_env));
env->num_sched_threads = (size_t)get_num_threads();
env->min_stack_size = get_min_stk_size();
env->logspec = copyenv(RUST_LOG);
env->check_claims = getenv(CHECK_CLAIMS) != NULL;
env->detailed_leaks = getenv(DETAILED_LEAKS) != NULL;
env->rust_seed = copyenv(RUST_SEED);
return env;
}
void
free_env(rust_env *env) {
free(env->logspec);
free(env->rust_seed);
free(env);
}