DWARF_LINENO(3)

πŸ“¦ version 15.1, in freebsd 14.5, freebsd 15.1, nixpkgs unstable

hiii bestie πŸ’– welcome to the DWARF_LINENO(3) library-functions-manual page. this is where a DWARF line descriptor (a Dwarf_Line) spills its specific line info into whatever your ret pointer points at. it's giving β€œtiny getter functions with main character energy” and honestly? obsessed. ✨

🌸 NAME 🌸

the whole squad, assembled: dwarf_lineaddr, dwarf_linebeginstatement, dwarf_lineblock, dwarf_lineendsequence, dwarf_lineno, dwarf_lineoff, dwarf_linesrc, and dwarf_line_srcfileno. their collective mission is retrieve information associated with a DWARF line descriptor. periodt. πŸ’…

πŸ“š LIBRARY πŸ“š

DWARF Access Library (libdwarf, -ldwarf) β€” that's the one, bestie. πŸŽ€

πŸ› οΈ SYNOPSIS πŸ› οΈ

#include <libdwarf.h>

int
dwarf_lineaddr(Dwarf_Line ln, Dwarf_Addr *ret, Dwarf_Error *err);

int
dwarf_linebeginstatement(Dwarf_Line ln, Dwarf_Bool *ret,
    Dwarf_Error *err);

int
dwarf_lineblock(Dwarf_Line ln, Dwarf_Bool *ret, Dwarf_Error *err);

int
dwarf_lineendsequence(Dwarf_Line ln, Dwarf_Bool *ret, Dwarf_Error *err);

int
dwarf_lineno(Dwarf_Line ln, Dwarf_Unsigned *ret, Dwarf_Error *err);

int
dwarf_lineoff(Dwarf_Line ln, Dwarf_Signed *ret, Dwarf_Error *err);

int
dwarf_linesrc(Dwarf_Line ln, char **ret, Dwarf_Error *err);

int
dwarf_line_srcfileno(Dwarf_Line ln, Dwarf_Unsigned *ret,
    Dwarf_Error *err);

πŸ’… DESCRIPTION πŸ’…

okay so the big picture: these functions retrieve specific line information associated with the line descriptor specified by argument ln, and store it in the location pointed to by argument ret. if argument err is not NULL, it will be used to store error information in case of an error. no cap, that's the whole setup. 🌈

  • dwarf_lineaddr() β€” stores the program address corresponding to the source line specified in argument ln into the location pointed to by argument ret. πŸ“
  • dwarf_linebeginstatement() β€” sets the location pointed to by argument ret to 1 if the source line specified by the line descriptor ln is the beginning of a statement, or to 0 otherwise. 🫢
  • dwarf_lineblock() β€” sets the location pointed to by argument ret to 1 if the source line specified by the line descriptor ln is the beginning of a basic block, or to 0 otherwise. 🧚
  • dwarf_lineendsequence() β€” sets the location pointed to by argument ret to 1 if the program address associated with the line descriptor ln is the address immediately following the end of a sequence of target machine instructions, or to 0 otherwise. πŸ”₯
  • dwarf_lineno() β€” stores the line number of the source line associated with the line descriptor ln into the location pointed to by argument ret. ⭐
  • dwarf_lineoff() β€” stores the column number within a line associated with descriptor ln into the location pointed to by argument ret. the retrieved column numbers are 1-based, with the value -1 indicating that column number information was not available. πŸ™ˆ
  • dwarf_linesrc() β€” stores a pointer to a NUL-terminated string containing the source file name associated with line descriptor ln into the location pointed to by argument ret. the full path of the source file is returned if possible. the memory used for the source file name string is managed by the DWARF(3) library and should not be directly freed by application code. instead, portable code should use dwarf_dealloc(3) to indicate that the string should be freed. πŸŽ€
  • dwarf_line_srcfileno() β€” stores the index of the source file associated with the line descriptor ln in the location pointed to by argument ret. the returned value is a 1-based index into the array of source file names returned by dwarf_srcfiles(3). πŸ’œ

βœ… RETURN VALUES βœ…

on success, these functions return DW_DLV_OK. in case of an error, they return DW_DLV_ERROR and set the argument err. periodt. πŸ’–

πŸ’€ ERRORS πŸ’€

these functions may fail with the following errors:

  • [DW_DLE_ARGUMENT] β€” either of the arguments ln or ret was NULL. 🫠
  • [DW_DLE_LINE_FILE_NUM_BAD] β€” the source file name associated with the line descriptor ln could not be retrieved by function dwarf_linesrc(). 😭

πŸ‘€ SEE ALSO πŸ‘€

go give these a peek, bestie:

mwah πŸ’‹ β€” source/version: Debian; date: February 5, 2011. now go treat your line descriptors right! 🫢

πŸ“¦ where this page comes from