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Diffstat (limited to 'gdb/dwarf2/line-header.h')
| -rw-r--r-- | gdb/dwarf2/line-header.h | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/gdb/dwarf2/line-header.h b/gdb/dwarf2/line-header.h new file mode 100644 index 0000000..08cf7b0 --- /dev/null +++ b/gdb/dwarf2/line-header.h @@ -0,0 +1,188 @@ +/* DWARF 2 debugging format support for GDB. + + Copyright (C) 1994-2020 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#ifndef DWARF2_LINE_HEADER_H +#define DWARF2_LINE_HEADER_H + +#include "gdbtypes.h" + +/* dir_index is 1-based in DWARF 4 and before, and is 0-based in DWARF 5 and + later. */ +typedef int dir_index; + +/* file_name_index is 1-based in DWARF 4 and before, and is 0-based in DWARF 5 + and later. */ +typedef int file_name_index; + +struct line_header; + +struct file_entry +{ + file_entry () = default; + + file_entry (const char *name_, dir_index d_index_, + unsigned int mod_time_, unsigned int length_) + : name (name_), + d_index (d_index_), + mod_time (mod_time_), + length (length_) + {} + + /* Return the include directory at D_INDEX stored in LH. Returns + NULL if D_INDEX is out of bounds. */ + const char *include_dir (const line_header *lh) const; + + /* The file name. Note this is an observing pointer. The memory is + owned by debug_line_buffer. */ + const char *name {}; + + /* The directory index (1-based). */ + dir_index d_index {}; + + unsigned int mod_time {}; + + unsigned int length {}; + + /* True if referenced by the Line Number Program. */ + bool included_p {}; + + /* The associated symbol table, if any. */ + struct symtab *symtab {}; +}; + +/* The line number information for a compilation unit (found in the + .debug_line section) begins with a "statement program header", + which contains the following information. */ +struct line_header +{ + line_header () + : offset_in_dwz {} + {} + + /* Add an entry to the include directory table. */ + void add_include_dir (const char *include_dir); + + /* Add an entry to the file name table. */ + void add_file_name (const char *name, dir_index d_index, + unsigned int mod_time, unsigned int length); + + /* Return the include dir at INDEX (0-based in DWARF 5 and 1-based before). + Returns NULL if INDEX is out of bounds. */ + const char *include_dir_at (dir_index index) const + { + int vec_index; + if (version >= 5) + vec_index = index; + else + vec_index = index - 1; + if (vec_index < 0 || vec_index >= m_include_dirs.size ()) + return NULL; + return m_include_dirs[vec_index]; + } + + bool is_valid_file_index (int file_index) + { + if (version >= 5) + return 0 <= file_index && file_index < file_names_size (); + return 1 <= file_index && file_index <= file_names_size (); + } + + /* Return the file name at INDEX (0-based in DWARF 5 and 1-based before). + Returns NULL if INDEX is out of bounds. */ + file_entry *file_name_at (file_name_index index) + { + int vec_index; + if (version >= 5) + vec_index = index; + else + vec_index = index - 1; + if (vec_index < 0 || vec_index >= m_file_names.size ()) + return NULL; + return &m_file_names[vec_index]; + } + + /* The indexes are 0-based in DWARF 5 and 1-based in DWARF 4. Therefore, + this method should only be used to iterate through all file entries in an + index-agnostic manner. */ + std::vector<file_entry> &file_names () + { return m_file_names; } + + /* Offset of line number information in .debug_line section. */ + sect_offset sect_off {}; + + /* OFFSET is for struct dwz_file associated with dwarf2_per_objfile. */ + unsigned offset_in_dwz : 1; /* Can't initialize bitfields in-class. */ + + unsigned int total_length {}; + unsigned short version {}; + unsigned int header_length {}; + unsigned char minimum_instruction_length {}; + unsigned char maximum_ops_per_instruction {}; + unsigned char default_is_stmt {}; + int line_base {}; + unsigned char line_range {}; + unsigned char opcode_base {}; + + /* standard_opcode_lengths[i] is the number of operands for the + standard opcode whose value is i. This means that + standard_opcode_lengths[0] is unused, and the last meaningful + element is standard_opcode_lengths[opcode_base - 1]. */ + std::unique_ptr<unsigned char[]> standard_opcode_lengths; + + int file_names_size () + { return m_file_names.size(); } + + /* The start and end of the statement program following this + header. These point into dwarf2_per_objfile->line_buffer. */ + const gdb_byte *statement_program_start {}, *statement_program_end {}; + + /* Return the full name of file number I in this object's file name + table. Use COMP_DIR as the name of the current directory of the + compilation. The result is allocated using xmalloc; the caller + is responsible for freeing it. */ + gdb::unique_xmalloc_ptr<char> file_full_name (int file, + const char *comp_dir); + + /* Return file name relative to the compilation directory of file + number I in this object's file name table. The result is + allocated using xmalloc; the caller is responsible for freeing + it. */ + gdb::unique_xmalloc_ptr<char> file_file_name (int file); + + private: + /* The include_directories table. Note these are observing + pointers. The memory is owned by debug_line_buffer. */ + std::vector<const char *> m_include_dirs; + + /* The file_names table. This is private because the meaning of indexes + differs among DWARF versions (The first valid index is 1 in DWARF 4 and + before, and is 0 in DWARF 5 and later). So the client should use + file_name_at method for access. */ + std::vector<file_entry> m_file_names; +}; + +typedef std::unique_ptr<line_header> line_header_up; + +inline const char * +file_entry::include_dir (const line_header *lh) const +{ + return lh->include_dir_at (d_index); +} + +#endif /* DWARF2_LINE_HEADER_H */ |