1 /* 2 * 3 * Copyright 2015 gRPC authors. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 */ 18 19 #ifndef GRPC_SLICE_H 20 #define GRPC_SLICE_H 21 22 #include <grpc/support/port_platform.h> 23 24 #include <grpc/impl/codegen/slice.h> 25 #include <grpc/support/sync.h> 26 27 #ifdef __cplusplus 28 extern "C" { 29 #endif 30 31 /** Increment the refcount of s. Requires slice is initialized. 32 Returns s. */ 33 GPRAPI grpc_slice grpc_slice_ref(grpc_slice s); 34 35 /** Decrement the ref count of s. If the ref count of s reaches zero, all 36 slices sharing the ref count are destroyed, and considered no longer 37 initialized. If s is ultimately derived from a call to grpc_slice_new(start, 38 len, dest) where dest!=NULL , then (*dest)(start) is called, else if s is 39 ultimately derived from a call to grpc_slice_new_with_len(start, len, dest) 40 where dest!=NULL , then (*dest)(start, len). Requires s initialized. */ 41 GPRAPI void grpc_slice_unref(grpc_slice s); 42 43 /** Copy slice - create a new slice that contains the same data as s */ 44 GPRAPI grpc_slice grpc_slice_copy(grpc_slice s); 45 46 /** Create a slice pointing at some data. Calls malloc to allocate a refcount 47 for the object, and arranges that destroy will be called with the pointer 48 passed in at destruction. */ 49 GPRAPI grpc_slice grpc_slice_new(void* p, size_t len, void (*destroy)(void*)); 50 51 /** Equivalent to grpc_slice_new, but with a separate pointer that is 52 passed to the destroy function. This function can be useful when 53 the data is part of a larger structure that must be destroyed when 54 the data is no longer needed. */ 55 GPRAPI grpc_slice grpc_slice_new_with_user_data(void* p, size_t len, 56 void (*destroy)(void*), 57 void* user_data); 58 59 /** Equivalent to grpc_slice_new, but with a two argument destroy function that 60 also takes the slice length. */ 61 GPRAPI grpc_slice grpc_slice_new_with_len(void* p, size_t len, 62 void (*destroy)(void*, size_t)); 63 64 /** Equivalent to grpc_slice_new(malloc(len), len, free), but saves one malloc() 65 call. 66 Aborts if malloc() fails. */ 67 GPRAPI grpc_slice grpc_slice_malloc(size_t length); 68 GPRAPI grpc_slice grpc_slice_malloc_large(size_t length); 69 70 #define GRPC_SLICE_MALLOC(len) grpc_slice_malloc(len) 71 72 /** Intern a slice: 73 74 The return value for two invocations of this function with the same sequence 75 of bytes is a slice which points to the same memory. */ 76 GPRAPI grpc_slice grpc_slice_intern(grpc_slice slice); 77 78 /** Create a slice by copying a string. 79 Does not preserve null terminators. 80 Equivalent to: 81 size_t len = strlen(source); 82 grpc_slice slice = grpc_slice_malloc(len); 83 memcpy(slice->data, source, len); */ 84 GPRAPI grpc_slice grpc_slice_from_copied_string(const char* source); 85 86 /** Create a slice by copying a buffer. 87 Equivalent to: 88 grpc_slice slice = grpc_slice_malloc(len); 89 memcpy(slice->data, source, len); */ 90 GPRAPI grpc_slice grpc_slice_from_copied_buffer(const char* source, size_t len); 91 92 /** Create a slice pointing to constant memory */ 93 GPRAPI grpc_slice grpc_slice_from_static_string(const char* source); 94 95 /** Create a slice pointing to constant memory */ 96 GPRAPI grpc_slice grpc_slice_from_static_buffer(const void* source, size_t len); 97 98 /** Return a result slice derived from s, which shares a ref count with \a s, 99 where result.data==s.data+begin, and result.length==end-begin. The ref count 100 of \a s is increased by one. Do not assign result back to \a s. 101 Requires s initialized, begin <= end, begin <= s.length, and 102 end <= source->length. */ 103 GPRAPI grpc_slice grpc_slice_sub(grpc_slice s, size_t begin, size_t end); 104 105 /** The same as grpc_slice_sub, but without altering the ref count */ 106 GPRAPI grpc_slice grpc_slice_sub_no_ref(grpc_slice s, size_t begin, size_t end); 107 108 /** Splits s into two: modifies s to be s[0:split], and returns a new slice, 109 sharing a refcount with s, that contains s[split:s.length]. 110 Requires s intialized, split <= s.length */ 111 GPRAPI grpc_slice grpc_slice_split_tail(grpc_slice* s, size_t split); 112 113 typedef enum { 114 GRPC_SLICE_REF_TAIL = 1, 115 GRPC_SLICE_REF_HEAD = 2, 116 GRPC_SLICE_REF_BOTH = 1 + 2 117 } grpc_slice_ref_whom; 118 119 /** The same as grpc_slice_split_tail, but with an option to skip altering 120 * refcounts (grpc_slice_split_tail_maybe_ref(..., true) is equivalent to 121 * grpc_slice_split_tail(...)) */ 122 GPRAPI grpc_slice grpc_slice_split_tail_maybe_ref(grpc_slice* s, size_t split, 123 grpc_slice_ref_whom ref_whom); 124 125 /** Splits s into two: modifies s to be s[split:s.length], and returns a new 126 slice, sharing a refcount with s, that contains s[0:split]. 127 Requires s intialized, split <= s.length */ 128 GPRAPI grpc_slice grpc_slice_split_head(grpc_slice* s, size_t split); 129 130 GPRAPI grpc_slice grpc_empty_slice(void); 131 132 GPRAPI uint32_t grpc_slice_default_hash_impl(grpc_slice s); 133 GPRAPI int grpc_slice_default_eq_impl(grpc_slice a, grpc_slice b); 134 135 GPRAPI int grpc_slice_eq(grpc_slice a, grpc_slice b); 136 137 /** Returns <0 if a < b, ==0 if a == b, >0 if a > b 138 The order is arbitrary, and is not guaranteed to be stable across different 139 versions of the API. */ 140 GPRAPI int grpc_slice_cmp(grpc_slice a, grpc_slice b); 141 GPRAPI int grpc_slice_str_cmp(grpc_slice a, const char* b); 142 143 /** return non-zero if the first blen bytes of a are equal to b */ 144 GPRAPI int grpc_slice_buf_start_eq(grpc_slice a, const void* b, size_t blen); 145 146 /** return the index of the last instance of \a c in \a s, or -1 if not found */ 147 GPRAPI int grpc_slice_rchr(grpc_slice s, char c); 148 GPRAPI int grpc_slice_chr(grpc_slice s, char c); 149 150 /** return the index of the first occurance of \a needle in \a haystack, or -1 151 if it's not found */ 152 GPRAPI int grpc_slice_slice(grpc_slice haystack, grpc_slice needle); 153 154 GPRAPI uint32_t grpc_slice_hash(grpc_slice s); 155 156 /** Do two slices point at the same memory, with the same length 157 If a or b is inlined, actually compares data */ 158 GPRAPI int grpc_slice_is_equivalent(grpc_slice a, grpc_slice b); 159 160 /** Return a slice pointing to newly allocated memory that has the same contents 161 * as \a s */ 162 GPRAPI grpc_slice grpc_slice_dup(grpc_slice a); 163 164 /** Return a copy of slice as a C string. Offers no protection against embedded 165 NULL's. Returned string must be freed with gpr_free. */ 166 GPRAPI char* grpc_slice_to_c_string(grpc_slice s); 167 168 #ifdef __cplusplus 169 } 170 #endif 171 172 #endif /* GRPC_SLICE_H */ 173
