From 51500eedefa492699668ced3e07e330a9a4d53ee Mon Sep 17 00:00:00 2001 From: Kenta Murata Date: Fri, 4 Dec 2020 15:50:13 +0900 Subject: memory_view.c: Add rb_memory_view_extract_item_members --- memory_view.c | 225 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 223 insertions(+), 2 deletions(-) (limited to 'memory_view.c') diff --git a/memory_view.c b/memory_view.c index 8b2a2c051d..2bf3eee107 100644 --- a/memory_view.c +++ b/memory_view.c @@ -12,6 +12,18 @@ #include "internal/util.h" #include "ruby/memory_view.h" +#if SIZEOF_INTPTR_T == SIZEOF_LONG_LONG +# define INTPTR2NUM LL2NUM +# define UINTPTR2NUM ULL2NUM +#elif SIZEOF_INTPTR_T == SIZEOF_LONG +# define INTPTR2NUM LONG2NUM +# define UINTPTR2NUM ULONG2NUM +#else +# define INTPTR2NUM INT2NUM +# define UINTPTR2NUM UINT2NUM +#endif + + #define STRUCT_ALIGNOF(T, result) do { \ (result) = RUBY_ALIGNOF(T); \ } while(0) @@ -394,13 +406,13 @@ calculate_padding(ssize_t total, ssize_t alignment_size) { ssize_t rb_memory_view_parse_item_format(const char *format, rb_memory_view_item_component_t **members, - ssize_t *n_members, const char **err) + size_t *n_members, const char **err) { if (format == NULL) return 1; VALUE error = Qnil; ssize_t total = 0; - ssize_t len = 0; + size_t len = 0; bool alignment = false; ssize_t max_alignment_size = 0; @@ -558,6 +570,215 @@ rb_memory_view_get_item_pointer(rb_memory_view_t *view, const ssize_t *indices) return ptr; } +static void +switch_endianness(uint8_t *buf, ssize_t len) +{ + RUBY_ASSERT(buf != NULL); + RUBY_ASSERT(len >= 0); + + uint8_t *p = buf; + uint8_t *q = buf + len - 1; + + while (q - p > 0) { + uint8_t t = *p; + *p = *q; + *q = t; + ++p; + --q; + } +} + +static inline VALUE +extract_item_member(const uint8_t *ptr, const rb_memory_view_item_component_t *member, const size_t i, + uint8_t *buf, const size_t buf_size) +{ + RUBY_ASSERT(ptr != NULL); + RUBY_ASSERT(member != NULL); + +#ifdef WORDS_BIGENDIAN + const bool native_endian_p = !member->little_endian_p; +#else + const bool native_endian_p = member->little_endian_p; +#endif + + const uint8_t *p = ptr + member->offset + i * member->size; + + if (member->format == 'c') { + return INT2FIX(*(char *)p); + } + else if (member->format == 'C') { + return INT2FIX(*(unsigned char *)p); + } + + const uint8_t *q = p; + + if (!native_endian_p) { + RUBY_ASSERT(buf != NULL); + MEMCPY(buf, p, uint8_t, member->size); + switch_endianness(buf, member->size); + q = buf; + } + + switch (member->format) { + case 's': + if (member->native_size_p) { + return INT2FIX(*(short *)q); + } + else { + return INT2FIX(*(int16_t *)q); + } + + case 'S': + case 'n': + case 'v': + if (member->native_size_p) { + return UINT2NUM(*(unsigned short *)q); + } + else { + return INT2FIX(*(uint16_t *)q); + } + + case 'i': + return INT2NUM(*(int *)q); + + case 'I': + return UINT2NUM(*(unsigned int *)q); + + case 'l': + if (member->native_size_p) { + return LONG2NUM(*(long *)q); + } + else { + return LONG2NUM(*(int32_t *)q); + } + + case 'L': + case 'N': + case 'V': + if (member->native_size_p) { + return ULONG2NUM(*(unsigned long *)q); + } + else { + return ULONG2NUM(*(uint32_t *)q); + } + + case 'f': + case 'e': + case 'g': + return DBL2NUM(*(float *)q); + + case 'q': + if (member->native_size_p) { + return LL2NUM(*(LONG_LONG *)q); + } + else { +#if SIZEOF_INT64_t == SIZEOF_LONG + return LONG2NUM(*(int64_t *)q); +#else + return LL2NUM(*(int64_t *)q); +#endif + } + + case 'Q': + if (member->native_size_p) { + return ULL2NUM(*(unsigned LONG_LONG *)q); + } + else { +#if SIZEOF_UINT64_t == SIZEOF_LONG + return ULONG2NUM(*(uint64_t *)q); +#else + return ULL2NUM(*(uint64_t *)q); +#endif + } + + case 'd': + case 'E': + case 'G': + return DBL2NUM(*(double *)q); + + case 'j': + return INTPTR2NUM(*(intptr_t *)q); + + case 'J': + return UINTPTR2NUM(*(uintptr_t *)q); + + default: + UNREACHABLE_RETURN(Qnil); + } +} + +/* Return a value of the extracted member. */ +VALUE +rb_memory_view_extract_item_member(const void *ptr, const rb_memory_view_item_component_t *member, const size_t i) +{ + if (ptr == NULL) return Qnil; + if (member == NULL) return Qnil; + if (i >= member->repeat) return Qnil; + +#ifdef WORDS_BIGENDIAN + const bool native_endian_p = !member->little_endian_p; +#else + const bool native_endian_p = member->little_endian_p; +#endif + + VALUE buf_v = 0; + uint8_t *buf; + if (!native_endian_p) { + buf = ALLOCV_N(uint8_t, buf_v, member->size); + } + + VALUE v = extract_item_member(ptr, member, i, buf, member->size); + + if (buf_v) ALLOCV_END(buf_v); + return v; +} + +/* Return a value that consists of item members. + * When an item is a single member, the return value is a single value. + * When an item consists of multiple members, an array will be returned. */ +VALUE +rb_memory_view_extract_item_members(const void *ptr, const rb_memory_view_item_component_t *members, const size_t n_members) +{ + if (ptr == NULL) return Qnil; + if (members == NULL) return Qnil; + if (n_members == 0) return Qnil; + + if (n_members == 1 && members[0].repeat == 1) { + return rb_memory_view_extract_item_member(ptr, members, 0); + } + + size_t i, max_size = 0; + bool need_switch_endianness_p = false; + for (i = 0; i < n_members; ++i) { + if (max_size < members[i].size) { + max_size = members[i].size; + } +#ifdef WORDS_BIGENDIAN + need_switch_endianness_p |= members[i].little_endian_p; +#else + need_switch_endianness_p |= !members[i].little_endian_p; +#endif + } + + VALUE buf_v = 0; + uint8_t *buf; + if (need_switch_endianness_p) { + buf = ALLOCV_N(uint8_t, buf_v, max_size); + } + + VALUE item = rb_ary_new(); + for (i = 0; i < n_members; ++i) { + size_t j; + for (j = 0; j < members[i].repeat; ++j) { + VALUE v = extract_item_member(ptr, &members[i], j, buf, max_size); + rb_ary_push(item, v); + } + } + + if (buf_v) ALLOCV_END(buf_v); + return item; +} + static const rb_memory_view_entry_t * lookup_memory_view_entry(VALUE klass) { -- cgit v1.2.1