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Add gensym

This commit is contained in:
bakpakin 2017-07-16 11:00:20 -04:00
parent 9187d4c1e2
commit 3ccd688438
4 changed files with 87 additions and 3 deletions

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@ -460,7 +460,6 @@ const uint8_t *gst_string_end(Gst *vm, uint8_t *str) {
check.data.string = (const uint8_t *) str;
cached = gst_cache_add(vm, check);
return cached.data.string;
}
/* Load a buffer as a string */
@ -481,6 +480,60 @@ const uint8_t *gst_string_b(Gst *vm, const uint8_t *buf, uint32_t len) {
}
}
static void inc_counter(uint8_t *digits, int base, int len) {
int i;
uint8_t carry = 1;
for (i = len - 1; i >= 0; --i) {
digits[i] += carry;
carry = 0;
if (digits[i] == base) {
digits[i] = 0;
carry = 1;
}
}
}
/* Generate a unique symbol */
const uint8_t *gst_string_bu(Gst *vm, const uint8_t *buf, uint32_t len) {
static const char base64[] =
"0123456789"
"abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"+-";
GstValue *bucket;
uint32_t hash;
uint8_t counter[6] = {63, 63, 63, 63, 63, 63};
/* Leave spaces for 6 base 64 digits and two dashes. That means 64^6 possible symbols, which
* is enough */
uint32_t newlen = len + 8;
uint32_t newbufsize = newlen + 2 * sizeof(uint32_t) + 1;
uint8_t *str = (uint8_t *)(gst_alloc(vm, newbufsize) + 2 * sizeof(uint32_t));
gst_string_length(str) = newlen;
gst_memcpy(str, buf, len);
str[len] = '-';
str[len + 1] = '-';
str[newlen] = 0;
uint8_t *saltbuf = str + len + 2;
int status = 1;
while (status) {
int i;
inc_counter(counter, 64, 6);
for (i = 0; i < 6; ++i)
saltbuf[i] = base64[counter[i]];
hash = gst_string_calchash(str, newlen);
bucket = gst_cache_strfind(vm, str, newlen, hash, &status);
}
gst_string_hash(str) = hash;
return gst_cache_add_bucket(vm, gst_wrap_string(str), bucket).data.string;
}
/* Generate a unique string from a cstring */
const uint8_t *gst_string_cu(Gst *vm, const char *s) {
uint32_t len = 0;
while (s[len]) ++len;
return gst_string_bu(vm, (const uint8_t *)s, len);
}
/* Load a c string */
const uint8_t *gst_string_c(Gst *vm, const char *str) {
uint32_t len = 0;

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@ -267,7 +267,7 @@ int gst_stl_slice(Gst *vm) {
x = gst_arg(vm, 0);
if (!gst_seq_view(x, &data, &length) &&
!gst_chararray_view(x, &cdata, &length)) {
gst_c_throwc(vm, "expected array or tuple");
gst_c_throwc(vm, "expected array/tuple/buffer/symbol/string");
}
/* Get from index */
@ -1011,6 +1011,22 @@ static int gst_stl_parse(Gst *vm) {
/* Compilation */
/***/
/* Generate a unique symbol */
static int gst_stl_gensym(Gst *vm) {
GstValue source = gst_arg(vm, 0);
const uint8_t *sym = NULL;
uint32_t len;
const uint8_t *data;
if (source.type == GST_NIL) {
sym = gst_string_cu(vm, "");
} else if (gst_chararray_view(source, &data, &len)) {
sym = gst_string_bu(vm, data, len);
} else {
gst_c_throwc(vm, "exepcted string/buffer/symbol/nil");
}
gst_c_return(vm, gst_wrap_symbol(sym));
}
/* Compile a value */
static int gst_stl_compile(Gst *vm) {
GstTable *env = vm->env;
@ -1073,6 +1089,7 @@ static const GstModuleItem std_module[] = {
{"parse-status", gst_stl_parser_status},
{"parse", gst_stl_parse},
/* Compile */
{"gensym", gst_stl_gensym},
{"getenv", gst_stl_getenv},
{"setenv", gst_stl_setenv},
{"compile", gst_stl_compile},
@ -1145,7 +1162,7 @@ void gst_stl_load(Gst *vm) {
gst_module_put(vm, "std", "stdin", gst_wrap_userdata(inp));
gst_module_put(vm, "std", "stdout", gst_wrap_userdata(outp));
gst_module_put(vm, "std", "stderr", gst_wrap_userdata(outp));
// Now merge
/* Now merge */
maybeEnv = gst_table_get(vm->modules, gst_string_cvs(vm, "std"));
gst_env_merge(vm, vm->env, maybeEnv.data.table);
}

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@ -111,6 +111,18 @@
(assert (= 110 (vargf 1 2 3 4)) "var arg tuple size 3")
(assert (= 210 (vargf 1 2 3 4 10 10 10 10 10 10 10 10 10 10)) "var arg large tuple")
# Gensym tests
(assert (not= (gensym) (gensym)) "two gensyms not equal")
(assert (not= (gensym 'abc) (gensym 'abc)) "two gensyms with arg not equal")
((fn []
(def syms (table))
(var count 0)
(while (< count 128)
(set! syms (gensym 'beep) true)
(varset! count (+ 1 count)))
(assert (= (length syms) 128) "many symbols")))
# report
(print "\n" num-tests-passed " of " num-tests-run " tests passed\n")

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@ -453,6 +453,8 @@ const uint8_t *gst_string_c(Gst *vm, const char *cstring);
GstValue gst_string_cv(Gst *vm, const char *string);
GstValue gst_string_cvs(Gst *vm, const char *string);
int gst_string_compare(const uint8_t *lhs, const uint8_t *rhs);
const uint8_t *gst_string_bu(Gst *vm, const uint8_t *buf, uint32_t len);
const uint8_t *gst_string_cu(Gst *vm, const char *s);
/****/
/* Struct functions */