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/*
* Copyright 2020 The Pigweed 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
*
* https://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.
*
* This linker script snippet declares the sections needed for string
* tokenization. All sections have type INFO so they are excluded from the final
* binary.
*
* The contents of this script can be copied into an existing linker script.
* Alternately, this file can be directly included in a linker script with an
* include directive. For example,
*
* INCLUDE path/to/modules/pw_tokenizer/pw_tokenizer_linker_sections.ld
*
* SECTIONS
* {
* (your existing linker sections)
* }
*/
SECTIONS
{
/*
* This section stores metadata that may be used during tokenized string
* decoding. This metadata describes properties that may affect how the
* tokenized string is encoded or decoded -- the maximum length of the hash
* function and the sizes of certain integer types.
*
* Metadata is declared as key-value pairs. See the metadata variable in
* tokenize.cc for further details.
*/
.pw_tokenizer_info 0x0 (INFO) :
{
KEEP(*(.pw_tokenizer_info))
}
/*
* Tokenized strings are stored in this section by default. In the compiled
* code, format string literals are replaced by a hash of the string contents
* and a compact argument list encoded in a uint32_t. The compiled code
* contains no references to the tokenized strings in this section.
*
* The section contents are declared with KEEP so that they are not removed
* from the ELF. These are never emitted in the final binary or loaded into
* memory.
*/
.pw_tokenized.default 0x0 (INFO) :
{
KEEP(*(.pw_tokenized.default.*))
}
/*
* Projects may define additional tokenization domains, if desired. Strings in
* different domains are stored in separate ELF sections so they can be
* processed separately by the token database tools.
*
* Use cases for domains include keeping large sets of strings separate to avoid
* collisions, or separating a small subset of strings that will use truncated
* tokens (e.g. 16-bit tokens instead of 32-bit tokens).
*
* Each tokenization domain in use must have a corresponding section in the
* linker script. As required, copy this section declaration and replace
* YOUR_CUSTOM_TOKENIZATION_DOMAIN with the the domain name.
.pw_tokenized.YOUR_CUSTOM_TOKENIZATION_DOMAIN 0x0 (INFO) :
{
KEEP(*(.pw_tokenized.YOUR_CUSTOM_TOKENIZATION_DOMAIN.*))
}
*/
}