jlapi.c

/*
  jlapi.c
  miscellaneous functions for users of libjulia.so, to handle initialization
  and the style of use where julia is not in control most of the time.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <libgen.h>
#include "julia.h"
extern char *julia_home;

DLLEXPORT char *jl_locate_sysimg(char *jlhome)
{
    if (jlhome == NULL) {
        char *julia_path = (char*)malloc(512);
        size_t path_size = 512;
        uv_exepath(julia_path, &path_size);
        julia_home = strdup(dirname(julia_path));
        free(julia_path);
    }
    else {
        julia_home = jlhome;
    }
    char path[512];
    snprintf(path, sizeof(path), "%s%s%s",
             julia_home, PATHSEPSTRING, JL_SYSTEM_IMAGE_PATH);
    return strdup(path);
}

DLLEXPORT void *jl_eval_string(char *str);

// argument is the usr/lib directory where libjulia is, or NULL to guess.
// if that doesn't work, try the full path to the "lib" directory that
// contains lib/julia/sys.ji
DLLEXPORT void jl_init(char *julia_home_dir)
{
    libsupport_init();
    char *image_file = jl_locate_sysimg(julia_home_dir);
    julia_init(image_file);
    jl_set_const(jl_core_module, jl_symbol("JULIA_HOME"),
                 jl_cstr_to_string(julia_home));
    jl_module_export(jl_core_module, jl_symbol("JULIA_HOME"));
    jl_eval_string("Base.reinit_stdio()");
    jl_eval_string("Base.librandom_init()");
    jl_eval_string("Base.init_sched()");
    jl_eval_string("Base.init_head_sched()");
    jl_eval_string("Base.init_load_path()");
}

#ifdef COPY_STACKS
void jl_switch_stack(jl_task_t *t, jl_jmp_buf *where);
extern jl_jmp_buf * volatile jl_jmp_target;
#endif

DLLEXPORT void *jl_eval_string(char *str)
{
#ifdef COPY_STACKS
    jl_root_task->stackbase = (char*)&str;
    if (jl_setjmp(jl_root_task->base_ctx, 1)) {
        jl_switch_stack(jl_current_task, jl_jmp_target);
    }
#endif
    jl_value_t *r;
    JL_TRY {
        jl_value_t *ast = jl_parse_input_line(str);
        JL_GC_PUSH(&ast);
        r = jl_toplevel_eval(ast);
        JL_GC_POP();
    }
    JL_CATCH {
        //jl_show(jl_stderr_obj(), jl_exception_in_transit);
        r = NULL;
    }
    return r;
}

DLLEXPORT jl_value_t *jl_exception_occurred(void)
{
    return jl_is_null(jl_exception_in_transit) ? NULL : 
        jl_exception_in_transit;
}

DLLEXPORT void jl_exception_clear(void)
{
    jl_exception_in_transit = (jl_value_t*)jl_null;
}

// get the name of a type as a string
DLLEXPORT const char *jl_typename_str(jl_value_t *v)
{
    if (jl_is_tuple(v))
        return "Tuple";
    return ((jl_datatype_t*)v)->name->name->name;
}

// get the name of typeof(v) as a string
DLLEXPORT const char *jl_typeof_str(jl_value_t *v)
{
    return jl_typename_str((jl_value_t*)jl_typeof(v));
}

DLLEXPORT void *jl_array_eltype(jl_value_t *a)
{
    return jl_tparam0(jl_typeof(a));
}

DLLEXPORT int jl_array_rank(jl_value_t *a)
{
    return jl_array_ndims(a);
}

DLLEXPORT size_t jl_array_size(jl_value_t *a, int d)
{
    return jl_array_dim(a, d);
}

DLLEXPORT void *jl_array_ptr(jl_array_t *a);

DLLEXPORT const char *jl_bytestring_ptr(jl_value_t *s)
{
    return jl_string_data(s);
}

DLLEXPORT jl_value_t *jl_call1(jl_function_t *f, jl_value_t *a)
{
    jl_value_t *v;
    JL_TRY {
        JL_GC_PUSH(&f,&a);
        v = jl_apply(f, &a, 1);
        JL_GC_POP();
    }
    JL_CATCH {
        v = NULL;
    }
    return v;
}

DLLEXPORT jl_value_t *jl_call2(jl_function_t *f, jl_value_t *a, jl_value_t *b)
{
    jl_value_t *v;
    JL_TRY {
        JL_GC_PUSH(&f,&a,&b);
        jl_value_t *args[2] = {a,b};
        v = jl_apply(f, args, 2);
        JL_GC_POP();
    }
    JL_CATCH {
        v = NULL;
    }
    return v;
}

JL_CALLABLE(jl_f_get_field);
DLLEXPORT jl_value_t *jl_get_field(jl_value_t *o, char *fld)
{
    jl_value_t *v;
    JL_TRY {
        jl_value_t *s = (jl_value_t*)jl_symbol(fld);
        jl_value_t *args[2] = {o, s};
        v = jl_f_get_field(NULL, args, 2);
    }
    JL_CATCH {
        v = NULL;
    }
    return v;
}

DLLEXPORT void jl_sigatomic_begin(void)
{
    JL_SIGATOMIC_BEGIN();
}

DLLEXPORT void jl_sigatomic_end(void)
{
    if (jl_defer_signal == 0)
        jl_error("sigatomic_end called in non-sigatomic region");
    JL_SIGATOMIC_END();
}