Coding Standards}. We encourage you to follow the applicable parts of
them too, especially chapter 5, ``Making the Best Use of C.'' Using a
different style won't cause actual problems, but it's ugly to see
-gratuitous differences in style from one function to another.
-
-@node Conditional Compilation
-@section Conditional Compilation
-
-Given the scope and complexity of your assignments this quarter, you
-may find it convenient while coding and debugging (and we will find it
-convenient while grading) to be able to independently turn different
-parts of the assignments on and off. To do this, choose a macro name
-and use it in conditional
-compilation directives, e.g.:
-
-@example
-#ifdef @var{NAME}
-@dots{}your code@dots{}
-#endif
-@end example
-
-In general, the code that you turn in must not depend on conditional
-compilation directives. Project code should be written so that all of
-the subproblems for the project function together, and it should
-compile properly without the need for any new macros to be defined.
-There are a few exceptions:
-
-@itemize @bullet
-@item
-Problem 1-2, @code{thread_join()}. Some other code expects
-@code{THREAD_JOIN_IMPLEMENTED} to be defined once you've implemented
-this function.
-
-@item
-Problem 1-4, the advanced scheduler. We must be able to turn this on
-and off with a compile-time directive. You must use the macro name we
-specify for that part. @xref{Problem 1-4 Advanced Scheduler}, for
-details.
-
-@item
-Code written for extra credit may be included conditionally. If the
-extra credit code changes the normally expected functionality of the
-code, then it @emph{must} be included conditionally, and it must not
-be enabled by default.
-@end itemize
-
-You can use @file{constants.h} in @file{pintos/src} to define macros
-for conditional compilation. We will replace the @file{constants.h}
-that you supply with one of our own when we test your code, so do not
-define anything important in it.
+gratuitous differences in style from one function to another. If your
+code is too ugly, it will cost you points.
+
+Please limit C source file lines to at most 79 characters long.
+
+Pintos comments sometimes refer to external standards or
+specifications by writing a name inside square brackets, like this:
+@code{[IA32-v3]}. These names refer to the reference names used in
+this documentation (@pxref{References}).
+
+If you remove existing Pintos code, please delete it from your source
+file entirely. Don't just put it into a comment or a conditional
+compilation directive, because that makes the resulting code hard to
+read. We're only going to do a compile in the directory for the current
+project, so you don't need to make sure that the previous projects also
+compile.
+
+Project code should be written so that all of the subproblems for the
+project function together, that is, without the need to rebuild with
+different macros defined, etc. If you do extra credit work that
+changes normal Pintos behavior so as to interfere with grading, then
+you must implement it so that it only acts that way when given a
+special command-line option of the form @option{-o @var{name}}, where
+@var{name} is a name of your choice. You can add such an option by
+modifying @func{argv_init} in @file{threads/init.c}.
@node C99
@section C99
@item <inttypes.h>
@file{<stdint.h>} is useful on its own, but it provides no way to pass
-the types it defines to @code{printf()} and related functions. This
+the types it defines to @func{printf} and related functions. This
header provides macros to help with that. For every
@code{int@var{n}_t} defined by @file{<stdint.h>}, it provides macros
@code{PRId@var{n}} and @code{PRIi@var{n}} for formatting values of
widths, etc.
@item <stdio.h>
-The @file{printf()} function has some new type modifiers for printing
+The @func{printf} function has some new type modifiers for printing
standard types:
@table @samp
@item t
For @code{ptrdiff_t} (e.g.@: @samp{%td}).
@end table
+
+Pintos @func{printf} also implements a nonstandard @samp{'} flag that
+group large numbers with commas to make them easier to read.
@end table
@node Unsafe String Functions
The worst offenders are intentionally not included in the Pintos C
library:
-@table @code
-@item strcpy()
+@table @func
+@item strcpy
When used carelessly this function can overflow the buffer reserved
-for its output string. Use @code{strlcpy()} instead. Refer to
+for its output string. Use @func{strlcpy} instead. Refer to
comments in its source code in @code{lib/string.c} for documentation.
-@item strncpy()
+@item strncpy
This function can leave its destination buffer without a null string
terminator and it has performance problems besides. Again, use
-@code{strlcpy()}.
+@func{strlcpy}.
-@item strcat()
-Same issue as @code{strcpy()}, but substitute @code{strlcat()}.
+@item strcat
+Same issue as @func{strcpy}. Use @func{strlcat} instead.
Again, refer to comments in its source code in @code{lib/string.c} for
documentation.
-@item strncat()
+@item strncat
The meaning of its buffer size argument often leads to problems.
-Again, use @code{strlcat()}.
+Again, use @func{strlcat}.
-@item strtok()
+@item strtok
Uses global data, so it is unsafe in threaded programs such as
-kernels. Use @code{strtok_r()} instead, and see its source code in
+kernels. Use @func{strtok_r} instead, and see its source code in
@code{lib/string.c} for documentation and an example.
-@item sprintf()
-Same issue as @code{strcpy()}. Use @code{snprintf()} instead. Refer
+@item sprintf
+Same issue as @func{strcpy}. Use @func{snprintf} instead. Refer
to comments in @code{lib/stdio.h} for documentation.
-@item vsprintf()
-Same issue as @code{strcpy()}. Use @code{vsnprintf()} instead.
+@item vsprintf
+Same issue as @func{strcpy}. Use @func{vsnprintf} instead.
@end table
If you try to use any of these functions, you should get a hint from
projects / pintos-anon / blobdiff