Make sym_table_find return the c-string in question directly

I think we fall into a few traps if we return an sv_t directly.  Think
intent is clearer by returning the c-string directly.
This commit is contained in:
2025-08-19 23:02:07 +01:00
parent e7f4b0440c
commit 6dfe3e72a1
3 changed files with 15 additions and 10 deletions

2
base.h
View File

@@ -77,7 +77,7 @@ typedef struct
u64 djb2(sv_t string);
void sym_table_init(sym_table_t *table);
sv_t sym_table_find(sym_table_t *table, sv_t sv);
char *sym_table_find(sym_table_t *table, sv_t sv);
void sym_table_cleanup(sym_table_t *table);
#endif

4
main.c
View File

@@ -50,8 +50,8 @@ int main(void)
for (u64 i = 0; i < ARRSIZE(words); ++i)
{
sv_t sv = sym_table_find(&table, SV(words[i], strlen(words[i])));
printf("%s => %p\n", words[i], sv.data);
char *ptr = sym_table_find(&table, SV(words[i], strlen(words[i])));
printf("%s => %p\n", words[i], ptr);
}
sym_table_cleanup(&table);

View File

@@ -32,7 +32,7 @@ void sym_table_init(sym_table_t *table)
vec_make((void **)&table->entries, table->capacity * sizeof(*table->entries));
}
sv_t sym_table_find(sym_table_t *table, sv_t sv)
char *sym_table_find(sym_table_t *table, sv_t sv)
{
// TODO: Deal with resizing this when table->count > table->size / 2
u64 index = djb2(sv) & (table->capacity - 1);
@@ -41,21 +41,26 @@ sv_t sym_table_find(sym_table_t *table, sv_t sv)
index = index & (table->capacity - 1), comp = table->entries[index])
// Is it present in the table?
if (sv.size == comp.size && strncmp(sv.data, comp.data, sv.size) == 0)
return comp;
break;
// Otherwise we need to duplicate and make it permanently interned
sv_t newsv = sv_copy(sv);
table->entries[index] = newsv;
++table->count;
// we couldn't find it in our linear search (worst case scenario)
if (!table->entries[index].data)
{
sv_t newsv = sv_copy(sv);
table->entries[index] = newsv;
++table->count;
}
return newsv;
return table->entries[index].data;
}
void sym_table_cleanup(sym_table_t *table)
{
// kill the data
for (u64 i = 0; i < table->capacity; ++i)
if (table->entries[i].data)
free(table->entries[i].data);
// kill the container
vec_free((void **)&table->entries);
memset(table, 0, sizeof(*table));
}