diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/ChangeLog | 7 | ||||
| -rw-r--r-- | include/ctf.h | 32 |
2 files changed, 33 insertions, 6 deletions
diff --git a/include/ChangeLog b/include/ChangeLog index de93394..c2e8031 100644 --- a/include/ChangeLog +++ b/include/ChangeLog @@ -1,3 +1,10 @@ +2019-07-11 Nick Alcock <nick.alcock@oracle.com> + + * ctf.h: Add object index and function index sections. Describe + them. Improve the description of the variable section and clarify + the constraints on backward-pointing type nodes. + (ctf_header): Add cth_objtidxoff, cth_funcidxoff. + 2019-07-06 Nick Alcock <nick.alcock@oracle.com> * ctf-api.h (ctf_cuname): New function. diff --git a/include/ctf.h b/include/ctf.h index 7e00005..f371cd7 100644 --- a/include/ctf.h +++ b/include/ctf.h @@ -52,10 +52,15 @@ extern "C" The CTF file or section itself has the following structure: - +--------+--------+---------+----------+----------+-------+--------+ - | file | type | data | function | variable | data | string | - | header | labels | objects | info | info | types | table | - +--------+--------+---------+----------+----------+-------+--------+ + +--------+--------+---------+----------+--------+----------+... + | file | type | data | function | object | function |... + | header | labels | objects | info | index | index |... + +--------+--------+---------+----------+--------+----------+... + + ...+----------+-------+--------+ + ...| variable | data | string | + ...| info | types | table | + +----------+-------+--------+ The file header stores a magic number and version information, encoding flags, and the byte offset of each of the sections relative to the end of the @@ -74,14 +79,27 @@ extern "C" For each data object, the type ID (a small integer) is recorded. For each function, the type ID of the return type and argument types is recorded. + For situations in which the order of the symbols in the symtab is not known, + a pair of optional indexes follow the data object and function info sections: + each of these is an array of strtab indexes, mapped 1:1 to the corresponding + data object / function info section, giving each entry in those sections a + name so that the linker can correlate them with final symtab entries and + reorder them accordingly (dropping the indexes in the process). + Variable records (as distinct from data objects) provide a modicum of support for non-ELF systems, mapping a variable name to a CTF type ID. The variable - names are sorted into ASCIIbetical order, permitting binary searching. + names are sorted into ASCIIbetical order, permitting binary searching. We do + not define how the consumer maps these variable names to addresses or + anything else, or indeed what these names represent: they might be names + looked up at runtime via dlsym() or names extracted at runtime by a debugger + or anything else the consumer likes. The data types section is a list of variable size records that represent each type, in order by their ID. The types themselves form a directed graph, where each node may contain one or more outgoing edges to other type nodes, - denoted by their ID. + denoted by their ID. Most type nodes are standalone or point backwards to + earlier nodes, but this is not required: nodes can point to later nodes, + particularly structure and union members. Strings are recorded as a string table ID (0 or 1) and a byte offset into the string table. String table 0 is the internal CTF string table. String table @@ -149,6 +167,8 @@ typedef struct ctf_header uint32_t cth_lbloff; /* Offset of label section. */ uint32_t cth_objtoff; /* Offset of object section. */ uint32_t cth_funcoff; /* Offset of function section. */ + uint32_t cth_objtidxoff; /* Offset of object index section. */ + uint32_t cth_funcidxoff; /* Offset of function index section. */ uint32_t cth_varoff; /* Offset of variable section. */ uint32_t cth_typeoff; /* Offset of type section. */ uint32_t cth_stroff; /* Offset of string section. */ |