| // Copyright 2021 gRPC authors. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/slice/slice_split.h" |
| |
| #include <string.h> |
| |
| #include <grpc/support/log.h> |
| |
| /** Finds the initial (\a begin) and final (\a end) offsets of the next |
| * substring from \a str + \a read_offset until the next \a sep or the end of \a |
| * str. |
| * |
| * Returns 1 and updates \a begin and \a end. Returns 0 otherwise. */ |
| static int slice_find_separator_offset(const grpc_slice str, const char* sep, |
| const size_t read_offset, size_t* begin, |
| size_t* end) { |
| size_t i; |
| const uint8_t* str_ptr = GRPC_SLICE_START_PTR(str) + read_offset; |
| const size_t str_len = GRPC_SLICE_LENGTH(str) - read_offset; |
| const size_t sep_len = strlen(sep); |
| if (str_len < sep_len) { |
| return 0; |
| } |
| |
| for (i = 0; i <= str_len - sep_len; i++) { |
| if (memcmp(str_ptr + i, sep, sep_len) == 0) { |
| *begin = read_offset; |
| *end = read_offset + i; |
| return 1; |
| } |
| } |
| return 0; |
| } |
| |
| static void skip_leading_trailing_spaces(const uint8_t* str_buffer, |
| size_t* begin, size_t* end) { |
| while (*begin < *end && str_buffer[*begin] == ' ') { |
| (*begin)++; |
| } |
| while (*begin < *end && str_buffer[*end - 1] == ' ') { |
| (*end)--; |
| } |
| } |
| |
| static void grpc_slice_split_inner(grpc_slice str, const char* sep, |
| grpc_slice_buffer* dst, bool no_space) { |
| const size_t sep_len = strlen(sep); |
| size_t begin, end; |
| const uint8_t* str_buffer = GRPC_SLICE_START_PTR(str); |
| size_t sep_pos; |
| |
| GPR_ASSERT(sep_len > 0); |
| |
| if (slice_find_separator_offset(str, sep, 0, &begin, &end) != 0) { |
| do { |
| sep_pos = end; |
| if (no_space) { |
| skip_leading_trailing_spaces(str_buffer, &begin, &end); |
| } |
| grpc_slice_buffer_add_indexed(dst, grpc_slice_sub(str, begin, end)); |
| } while (slice_find_separator_offset(str, sep, sep_pos + sep_len, &begin, |
| &end) != 0); |
| begin = sep_pos + sep_len; |
| end = GRPC_SLICE_LENGTH(str); |
| if (no_space) { |
| skip_leading_trailing_spaces(str_buffer, &begin, &end); |
| } |
| grpc_slice_buffer_add_indexed(dst, grpc_slice_sub(str, begin, end)); |
| } else { /* no sep found, add whole input */ |
| begin = 0; |
| end = GRPC_SLICE_LENGTH(str); |
| if (no_space) { |
| skip_leading_trailing_spaces(str_buffer, &begin, &end); |
| } |
| grpc_slice_buffer_add_indexed(dst, grpc_slice_sub(str, begin, end)); |
| } |
| } |
| |
| void grpc_slice_split(grpc_slice str, const char* sep, grpc_slice_buffer* dst) { |
| grpc_slice_split_inner(str, sep, dst, false); |
| } |
| |
| void grpc_slice_split_without_space(grpc_slice str, const char* sep, |
| grpc_slice_buffer* dst) { |
| grpc_slice_split_inner(str, sep, dst, true); |
| } |