Menu
Search

Library Reference

version 2.108.0

overview

Report a bug
If you spot a problem with this page, click here to create a Bugzilla issue.
Improve this page
Quickly fork, edit online, and submit a pull request for this page. Requires a signed-in GitHub account. This works well for small changes. If you'd like to make larger changes you may want to consider using a local clone.

dmd.chkformat

Check the arguments to printf and scanf against the format string.
Authors:
Walter Bright
License:
Boost License 1.0

Source chkformat.d

Documentation https://dlang.org/phobos/dmd_chkformat.html

Coverage https://codecov.io/gh/dlang/dmd/src/master/src/dmd/chkformat.d

bool checkPrintfFormat(const ref Loc loc, scope const char[] format, scope Expression[] args, bool isVa_list, ErrorSink eSink);
Check that arguments to a printf format string are compatible with that string. Issue errors for incompatibilities.
Follows the C99 specification for printf.
Takes a generous, rather than strict, view of compatiblity. For example, an unsigned value can be formatted with a signed specifier.
Diagnosed incompatibilities are:
  1. incompatible sizes which will cause argument misalignment
  2. deferencing arguments that are not pointers
  3. insufficient number of arguments
  4. struct arguments
  5. array and slice arguments
  6. non-pointer arguments to s specifier
  7. non-standard formats
  8. undefined behavior per C99
Per the C Standard, extra arguments are ignored.
No attempt is made to fix the arguments or the format string.
Parameters:
Loc loc location for error messages
char[] format format string
Expression[] args arguments to match with format string
bool isVa_list if a "v" function (format check only)
ErrorSink eSink where the error messages go
Returns:
true if errors occurred

References C99 7.19.6.1 https://www.cplusplus.com/reference/cstdio/printf/

bool checkScanfFormat(const ref Loc loc, scope const char[] format, scope Expression[] args, bool isVa_list, ErrorSink eSink);
Check that arguments to a scanf format string are compatible with that string. Issue errors for incompatibilities.
Follows the C99 specification for scanf.
Takes a generous, rather than strict, view of compatiblity. For example, an unsigned value can be formatted with a signed specifier.
Diagnosed incompatibilities are:
  1. incompatible sizes which will cause argument misalignment
  2. deferencing arguments that are not pointers
  3. insufficient number of arguments
  4. struct arguments
  5. array and slice arguments
  6. non-standard formats
  7. undefined behavior per C99
Per the C Standard, extra arguments are ignored.
No attempt is made to fix the arguments or the format string.
Parameters:
Loc loc location for error messages
char[] format format string
Expression[] args arguments to match with format string
bool isVa_list if a "v" function (format check only)
ErrorSink eSink where the error messages go
Returns:
true if errors occurred

References C99 7.19.6.2 https://www.cplusplus.com/reference/cstdio/scanf/