Daniel P. Berrangé <berra...@redhat.com> writes:
> Signed-off-by: Daniel P. Berrangé <berra...@redhat.com> Reviewed-by: Alex Bennée <alex.ben...@linaro.org> > --- > CODING_STYLE => CODING_STYLE.rst | 121 +++++++++++++++++++----------- > HACKING => HACKING.rst | 123 +++++++++++++++++++++---------- > README => README.rst | 47 +++++++----- > 3 files changed, 190 insertions(+), 101 deletions(-) > rename CODING_STYLE => CODING_STYLE.rst (72%) > rename HACKING => HACKING.rst (79%) > rename README => README.rst (84%) > > diff --git a/CODING_STYLE b/CODING_STYLE.rst > similarity index 72% > rename from CODING_STYLE > rename to CODING_STYLE.rst > index cb8edcbb36..713357cb80 100644 > --- a/CODING_STYLE > +++ b/CODING_STYLE.rst > @@ -1,10 +1,14 @@ > +================= > QEMU Coding Style > ================= > > +.. contents:: Table of Contents > + > Please use the script checkpatch.pl in the scripts directory to check > patches before submitting. > > -1. Whitespace > +Whitespace > +========== > > Of course, the most important aspect in any coding style is whitespace. > Crusty old coders who have trouble spotting the glasses on their noses > @@ -16,26 +20,27 @@ QEMU indents are four spaces. Tabs are never used, > except in Makefiles > where they have been irreversibly coded into the syntax. > Spaces of course are superior to tabs because: > > - - You have just one way to specify whitespace, not two. Ambiguity breeds > - mistakes. > - - The confusion surrounding 'use tabs to indent, spaces to justify' is gone. > - - Tab indents push your code to the right, making your screen seriously > - unbalanced. > - - Tabs will be rendered incorrectly on editors who are misconfigured not > - to use tab stops of eight positions. > - - Tabs are rendered badly in patches, causing off-by-one errors in almost > - every line. > - - It is the QEMU coding style. > +* You have just one way to specify whitespace, not two. Ambiguity breeds > + mistakes. > +* The confusion surrounding 'use tabs to indent, spaces to justify' is gone. > +* Tab indents push your code to the right, making your screen seriously > + unbalanced. > +* Tabs will be rendered incorrectly on editors who are misconfigured not > + to use tab stops of eight positions. > +* Tabs are rendered badly in patches, causing off-by-one errors in almost > + every line. > +* It is the QEMU coding style. > > Do not leave whitespace dangling off the ends of lines. > > -1.1 Multiline Indent > +Multiline Indent > +---------------- > > There are several places where indent is necessary: > > - - if/else > - - while/for > - - function definition & call > +* if/else > +* while/for > +* function definition & call > > When breaking up a long line to fit within line width, we need a proper > indent > for the following lines. > @@ -45,6 +50,8 @@ opening parenthesis of the first. > > For example: > > +.. code-block:: c > + > if (a == 1 && > b == 2) { > > @@ -53,12 +60,13 @@ For example: > > In case of function, there are several variants: > > - * 4 spaces indent from the beginning > - * align the secondary lines just after the opening parenthesis of the > - first > +* 4 spaces indent from the beginning > +* align the secondary lines just after the opening parenthesis of the first > > For example: > > +.. code-block:: c > + > do_something(x, y, > z); > > @@ -68,7 +76,8 @@ For example: > do_something(x, do_another(y, > z)); > > -2. Line width > +Line width > +========== > > Lines should be 80 characters; try not to make them longer. > > @@ -77,16 +86,18 @@ that use long function or symbol names. Even in that > case, do not make > lines much longer than 80 characters. > > Rationale: > - - Some people like to tile their 24" screens with a 6x4 matrix of 80x24 > - xterms and use vi in all of them. The best way to punish them is to > - let them keep doing it. > - - Code and especially patches is much more readable if limited to a sane > - line length. Eighty is traditional. > - - The four-space indentation makes the most common excuse ("But look > - at all that white space on the left!") moot. > - - It is the QEMU coding style. > > -3. Naming > +* Some people like to tile their 24" screens with a 6x4 matrix of 80x24 > + xterms and use vi in all of them. The best way to punish them is to > + let them keep doing it. > +* Code and especially patches is much more readable if limited to a sane > + line length. Eighty is traditional. > +* The four-space indentation makes the most common excuse ("But look > + at all that white space on the left!") moot. > +* It is the QEMU coding style. > + > +Naming > +====== > > Variables are lower_case_with_underscores; easy to type and read. Structured > type names are in CamelCase; harder to type but standing out. Enum type > @@ -95,10 +106,11 @@ names are lower_case_with_underscores_ending_with_a_t, > like the POSIX > uint64_t and family. Note that this last convention contradicts POSIX > and is therefore likely to be changed. > > -When wrapping standard library functions, use the prefix qemu_ to alert > +When wrapping standard library functions, use the prefix ``qemu_`` to alert > readers that they are seeing a wrapped version; otherwise avoid this prefix. > > -4. Block structure > +Block structure > +=============== > > Every indented statement is braced; even if the block contains just one > statement. The opening brace is on the line that contains the control > @@ -106,6 +118,8 @@ flow statement that introduces the new block; the closing > brace is on the > same line as the else keyword, or on a line by itself if there is no else > keyword. Example: > > +.. code-block:: c > + > if (a == 5) { > printf("a was 5.\n"); > } else if (a == 6) { > @@ -121,6 +135,8 @@ statement. > An exception is the opening brace for a function; for reasons of tradition > and clarity it comes on a line by itself: > > +.. code-block:: c > + > void a_function(void) > { > do_something(); > @@ -130,7 +146,8 @@ Rationale: a consistent (except for functions...) bracing > style reduces > ambiguity and avoids needless churn when lines are added or removed. > Furthermore, it is the QEMU coding style. > > -5. Declarations > +Declarations > +============ > > Mixed declarations (interleaving statements and declarations within > blocks) are generally not allowed; declarations should be at the beginning > @@ -142,11 +159,14 @@ be placed at the top of the block even if there are > statements above. > On the other hand, however, it's often best to move that #ifdef/#ifndef > block to a separate function altogether. > > -6. Conditional statements > +Conditional statements > +====================== > > When comparing a variable for (in)equality with a constant, list the > constant on the right, as in: > > +.. code-block:: c > + > if (a == 1) { > /* Reads like: "If a equals 1" */ > do_something(); > @@ -156,19 +176,24 @@ Rationale: Yoda conditions (as in 'if (1 == a)') are > awkward to read. > Besides, good compilers already warn users when '==' is mis-typed as '=', > even when the constant is on the right. > > -7. Comment style > +Comment style > +============= > > -We use traditional C-style /* */ comments and avoid // comments. > +We use traditional C-style /``*`` ``*``/ comments and avoid // comments. > > Rationale: The // form is valid in C99, so this is purely a matter of > consistency of style. The checkpatch script will warn you about this. > > Multiline comment blocks should have a row of stars on the left, > -and the initial /* and terminating */ both on their own lines: > +and the initial /``*`` and terminating ``*``/ both on their own lines: > + > +.. code-block:: c > + > /* > * like > * this > */ > + > This is the same format required by the Linux kernel coding style. > > (Some of the existing comments in the codebase use the GNU Coding > @@ -180,24 +205,32 @@ comment anyway.) > Rationale: Consistency, and ease of visually picking out a multiline > comment from the surrounding code. > > -8. trace-events style > +trace-events style > +================== > > -8.1 0x prefix > +0x prefix > +--------- > > In trace-events files, use a '0x' prefix to specify hex numbers, as in: > > -some_trace(unsigned x, uint64_t y) "x 0x%x y 0x" PRIx64 > +.. code-block:: > + > + some_trace(unsigned x, uint64_t y) "x 0x%x y 0x" PRIx64 > > An exception is made for groups of numbers that are hexadecimal by > convention and separated by the symbols '.', '/', ':', or ' ' (such as > PCI bus id): > > -another_trace(int cssid, int ssid, int dev_num) "bus id: %x.%x.%04x" > +.. code-block:: > + > + another_trace(int cssid, int ssid, int dev_num) "bus id: %x.%x.%04x" > > However, you can use '0x' for such groups if you want. Anyway, be sure that > it is obvious that numbers are in hex, ex.: > > -data_dump(uint8_t c1, uint8_t c2, uint8_t c3) "bytes (in hex): %02x %02x > %02x" > +.. code-block:: > + > + data_dump(uint8_t c1, uint8_t c2, uint8_t c3) "bytes (in hex): %02x %02x > %02x" > > Rationale: hex numbers are hard to read in logs when there is no 0x prefix, > especially when (occasionally) the representation doesn't contain any letters > @@ -205,12 +238,14 @@ and especially in one line with other decimal numbers. > Number groups are allowed > to not use '0x' because for some things notations like %x.%x.%x are used not > only in Qemu. Also dumping raw data bytes with '0x' is less readable. > > -8.2 '#' printf flag > +'#' printf flag > +--------------- > > Do not use printf flag '#', like '%#x'. > > Rationale: there are two ways to add a '0x' prefix to printed number: > '0x%...' > and '%#...'. For consistency the only one way should be used. Arguments for > '0x%' are: > - - it is more popular > - - '%#' omits the 0x for the value 0 which makes output inconsistent > + > +* it is more popular > +* '%#' omits the 0x for the value 0 which makes output inconsistent > diff --git a/HACKING b/HACKING.rst > similarity index 79% > rename from HACKING > rename to HACKING.rst > index 097d482603..668fc420c3 100644 > --- a/HACKING > +++ b/HACKING.rst > @@ -1,19 +1,32 @@ > -1. Preprocessor > +============ > +QEMU Hacking > +============ > > -1.1. Variadic macros > +.. contents:: Table of Contents > + > +Preprocessor > +============ > + > +Variadic macros > +--------------- > > For variadic macros, stick with this C99-like syntax: > > -#define DPRINTF(fmt, ...) \ > - do { printf("IRQ: " fmt, ## __VA_ARGS__); } while (0) > +.. code-block:: c > > -1.2. Include directives > + #define DPRINTF(fmt, ...) \ > + do { printf("IRQ: " fmt, ## __VA_ARGS__); } while (0) > + > +Include directives > +------------------ > > Order include directives as follows: > > -#include "qemu/osdep.h" /* Always first... */ > -#include <...> /* then system headers... */ > -#include "..." /* and finally QEMU headers. */ > +.. code-block:: c > + > + #include "qemu/osdep.h" /* Always first... */ > + #include <...> /* then system headers... */ > + #include "..." /* and finally QEMU headers. */ > > The "qemu/osdep.h" header contains preprocessor macros that affect the > behavior > of core system headers like <stdint.h>. It must be the first include so that > @@ -23,12 +36,14 @@ that QEMU depends on. > Do not include "qemu/osdep.h" from header files since the .c file will have > already included it. > > -2. C types > +C types > +======= > > It should be common sense to use the right type, but we have collected > a few useful guidelines here. > > -2.1. Scalars > +Scalars > +------- > > If you're using "int" or "long", odds are good that there's a better type. > If a variable is counting something, it should be declared with an > @@ -68,8 +83,8 @@ it may be 32 or 64 bits depending on which target is being > built. It should > therefore be used only in target-specific code, and in some > performance-critical built-per-target core code such as the TLB code. > There is also a signed version, target_long. > -abi_ulong is for the *-user targets, and represents a type the size of > -'void *' in that target's ABI. (This may not be the same as the size of a > +abi_ulong is for the ``*``-user targets, and represents a type the size of > +'void ``*``' in that target's ABI. (This may not be the same as the size of a > full CPU virtual address in the case of target ABIs which use 32 bit pointers > on 64 bit CPUs, like sparc32plus.) Definitions of structures that must match > the target's ABI must use this type for anything that on the target is > defined > @@ -89,7 +104,8 @@ Finally, while using descriptive types is important, be > careful not to > go overboard. If whatever you're doing causes warnings, or requires > casts, then reconsider or ask for help. > > -2.2. Pointers > +Pointers > +-------- > > Ensure that all of your pointers are "const-correct". > Unless a pointer is used to modify the pointed-to storage, > @@ -99,7 +115,8 @@ importantly, if we're diligent about this, when you see a > non-const > pointer, you're guaranteed that it is used to modify the storage > it points to, or it is aliased to another pointer that is. > > -2.3. Typedefs > +Typedefs > +-------- > > Typedefs are used to eliminate the redundant 'struct' keyword, since type > names have a different style than other identifiers ("CamelCase" versus > @@ -114,11 +131,14 @@ definitions instead of typedefs in headers and function > prototypes; this > avoids problems with duplicated typedefs and reduces the need to include > headers from other headers. > > -2.4. Reserved namespaces in C and POSIX > +Reserved namespaces in C and POSIX > +---------------------------------- > + > Underscore capital, double underscore, and underscore 't' suffixes should be > avoided. > > -3. Low level memory management > +Low level memory management > +=========================== > > Use of the malloc/free/realloc/calloc/valloc/memalign/posix_memalign > APIs is not allowed in the QEMU codebase. Instead of these routines, > @@ -130,36 +150,51 @@ Please note that g_malloc will exit on allocation > failure, so there > is no need to test for failure (as you would have to with malloc). > Calling g_malloc with a zero size is valid and will return NULL. > > -Prefer g_new(T, n) instead of g_malloc(sizeof(T) * n) for the following > +Prefer g_new(T, n) instead of g_malloc(sizeof(T) ``*`` n) for the following > reasons: > > - a. It catches multiplication overflowing size_t; > - b. It returns T * instead of void *, letting compiler catch more type > - errors. > +* It catches multiplication overflowing size_t; > +* It returns T ``*`` instead of void ``*``, letting compiler catch more type > errors. > + > +Declarations like > + > +.. code-block:: c > + > + T *v = g_malloc(sizeof(*v)) > > -Declarations like T *v = g_malloc(sizeof(*v)) are acceptable, though. > +are acceptable, though. > > Memory allocated by qemu_memalign or qemu_blockalign must be freed with > qemu_vfree, since breaking this will cause problems on Win32. > > -4. String manipulation > +String manipulation > +=================== > > Do not use the strncpy function. As mentioned in the man page, it does *not* > guarantee a NULL-terminated buffer, which makes it extremely dangerous to > use. > It also zeros trailing destination bytes out to the specified length. > Instead, > use this similar function when possible, but note its different signature: > -void pstrcpy(char *dest, int dest_buf_size, const char *src) > + > +.. code-block:: c > + > + void pstrcpy(char *dest, int dest_buf_size, const char *src) > > Don't use strcat because it can't check for buffer overflows, but: > -char *pstrcat(char *buf, int buf_size, const char *s) > + > +.. code-block:: c > + > + char *pstrcat(char *buf, int buf_size, const char *s) > > The same limitation exists with sprintf and vsprintf, so use snprintf and > vsnprintf. > > QEMU provides other useful string functions: > -int strstart(const char *str, const char *val, const char **ptr) > -int stristart(const char *str, const char *val, const char **ptr) > -int qemu_strnlen(const char *s, int max_len) > + > +.. code-block:: c > + > + int strstart(const char *str, const char *val, const char **ptr) > + int stristart(const char *str, const char *val, const char **ptr) > + int qemu_strnlen(const char *s, int max_len) > > There are also replacement character processing macros for isxyz and toxyz, > so instead of e.g. isalnum you should use qemu_isalnum. > @@ -167,7 +202,8 @@ so instead of e.g. isalnum you should use qemu_isalnum. > Because of the memory management rules, you must use g_strdup/g_strndup > instead of plain strdup/strndup. > > -5. Printf-style functions > +Printf-style functions > +====================== > > Whenever you add a new printf-style function, i.e., one with a format > string argument and following "..." in its prototype, be sure to use > @@ -177,12 +213,14 @@ This makes it so gcc's -Wformat and -Wformat-security > options can do > their jobs and cross-check format strings with the number and types > of arguments. > > -6. C standard, implementation defined and undefined behaviors > +C standard, implementation defined and undefined behaviors > +========================================================== > > C code in QEMU should be written to the C99 language specification. A copy > of the final version of the C99 standard with corrigenda TC1, TC2, and TC3 > included, formatted as a draft, can be downloaded from: > - http://www.open-std.org/jtc1/sc22/WG14/www/docs/n1256.pdf > + > + `<http://www.open-std.org/jtc1/sc22/WG14/www/docs/n1256.pdf>`_ > > The C language specification defines regions of undefined behavior and > implementation defined behavior (to give compiler authors enough leeway to > @@ -193,17 +231,20 @@ argument...) However there are a few areas where we > allow ourselves to > assume certain behaviors because in practice all the platforms we care about > behave in the same way and writing strictly conformant code would be > painful. These are: > - * you may assume that integers are 2s complement representation > - * you may assume that right shift of a signed integer duplicates > - the sign bit (ie it is an arithmetic shift, not a logical shift) > + > +* you may assume that integers are 2s complement representation > +* you may assume that right shift of a signed integer duplicates > + the sign bit (ie it is an arithmetic shift, not a logical shift) > > In addition, QEMU assumes that the compiler does not use the latitude > given in C99 and C11 to treat aspects of signed '<<' as undefined, as > documented in the GNU Compiler Collection manual starting at version 4.0. > > -7. Error handling and reporting > +Error handling and reporting > +============================ > > -7.1 Reporting errors to the human user > +Reporting errors to the human user > +---------------------------------- > > Do not use printf(), fprintf() or monitor_printf(). Instead, use > error_report() or error_vreport() from error-report.h. This ensures the > @@ -214,10 +255,11 @@ Use error_printf() & friends to print additional > information. > > error_report() prints the current location. In certain common cases > like command line parsing, the current location is tracked > -automatically. To manipulate it manually, use the loc_*() from > +automatically. To manipulate it manually, use the loc_``*``() from > error-report.h. > > -7.2 Propagating errors > +Propagating errors > +------------------ > > An error can't always be reported to the user right where it's detected, > but often needs to be propagated up the call chain to a place that can > @@ -233,16 +275,17 @@ error, non-negative / -errno, non-null / null, or Error > objects. > Example: when a function returns a non-null pointer on success, and it > can fail only in one way (as far as the caller is concerned), returning > null on failure is just fine, and certainly simpler and a lot easier on > -the eyes than propagating an Error object through an Error ** parameter. > +the eyes than propagating an Error object through an Error ``*````*`` > parameter. > > Example: when a function's callers need to report details on failure > -only the function really knows, use Error **, and set suitable errors. > +only the function really knows, use Error ``*````*``, and set suitable > errors. > > Do not report an error to the user when you're also returning an error > for somebody else to handle. Leave the reporting to the place that > consumes the error returned. > > -7.3 Handling errors > +Handling errors > +--------------- > > Calling exit() is fine when handling configuration errors during > startup. It's problematic during normal operation. In particular, > diff --git a/README b/README.rst > similarity index 84% > rename from README > rename to README.rst > index 441c33eb2f..9ff2877416 100644 > --- a/README > +++ b/README.rst > @@ -1,5 +1,6 @@ > - QEMU README > - =========== > +=========== > +QEMU README > +=========== > > QEMU is a generic and open source machine & userspace emulator and > virtualizer. > @@ -37,6 +38,9 @@ QEMU is multi-platform software intended to be buildable on > all modern > Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety > of other UNIX targets. The simple steps to build QEMU are: > > + > +.. code-block:: shell > + > mkdir build > cd build > ../configure > @@ -44,9 +48,9 @@ of other UNIX targets. The simple steps to build QEMU are: > > Additional information can also be found online via the QEMU website: > > - https://qemu.org/Hosts/Linux > - https://qemu.org/Hosts/Mac > - https://qemu.org/Hosts/W32 > +* `<https://qemu.org/Hosts/Linux>`_ > +* `<https://qemu.org/Hosts/Mac>`_ > +* `<https://qemu.org/Hosts/W32>`_ > > > Submitting patches > @@ -54,24 +58,29 @@ Submitting patches > > The QEMU source code is maintained under the GIT version control system. > > +.. code-block:: shell > + > git clone https://git.qemu.org/git/qemu.git > > When submitting patches, one common approach is to use 'git > format-patch' and/or 'git send-email' to format & send the mail to the > qemu-devel@nongnu.org mailing list. All patches submitted must contain > a 'Signed-off-by' line from the author. Patches should follow the > -guidelines set out in the HACKING and CODING_STYLE files. > +guidelines set out in the HACKING.rst and CODING_STYLE.rst files. > > Additional information on submitting patches can be found online via > the QEMU website > > - https://qemu.org/Contribute/SubmitAPatch > - https://qemu.org/Contribute/TrivialPatches > +* `<https://qemu.org/Contribute/SubmitAPatch>`_ > +* `<https://qemu.org/Contribute/TrivialPatches>`_ > > The QEMU website is also maintained under source control. > > +.. code-block:: shell > + > git clone https://git.qemu.org/git/qemu-web.git > - https://www.qemu.org/2017/02/04/the-new-qemu-website-is-up/ > + > +* `<https://www.qemu.org/2017/02/04/the-new-qemu-website-is-up/>`_ > > A 'git-publish' utility was created to make above process less > cumbersome, and is highly recommended for making regular contributions, > @@ -82,10 +91,12 @@ manually for once. > > For installation instructions, please go to > > - https://github.com/stefanha/git-publish > +* `<https://github.com/stefanha/git-publish>`_ > > The workflow with 'git-publish' is: > > +.. code-block:: shell > + > $ git checkout master -b my-feature > $ # work on new commits, add your 'Signed-off-by' lines to each > $ git publish > @@ -95,6 +106,8 @@ back to it in the future. > > Sending v2: > > +.. code-block:: shell > + > $ git checkout my-feature # same topic branch > $ # making changes to the commits (using 'git rebase', for example) > $ git publish > @@ -109,7 +122,7 @@ The QEMU project uses Launchpad as its primary upstream > bug tracker. Bugs > found when running code built from QEMU git or upstream released sources > should be reported via: > > - https://bugs.launchpad.net/qemu/ > +* `<https://bugs.launchpad.net/qemu/>`_ > > If using QEMU via an operating system vendor pre-built binary package, it > is preferable to report bugs to the vendor's own bug tracker first. If > @@ -118,7 +131,7 @@ reported via launchpad. > > For additional information on bug reporting consult: > > - https://qemu.org/Contribute/ReportABug > +* `<https://qemu.org/Contribute/ReportABug>`_ > > > Contact > @@ -127,13 +140,11 @@ Contact > The QEMU community can be contacted in a number of ways, with the two > main methods being email and IRC > > - - qemu-devel@nongnu.org > - https://lists.nongnu.org/mailman/listinfo/qemu-devel > - - #qemu on irc.oftc.net > +* `<mailto:qemu-devel@nongnu.org>`_ > +* `<https://lists.nongnu.org/mailman/listinfo/qemu-devel>`_ > +* #qemu on irc.oftc.net > > Information on additional methods of contacting the community can be > found online via the QEMU website: > > - https://qemu.org/Contribute/StartHere > - > --- End > +* `<https://qemu.org/Contribute/StartHere>`_ -- Alex Bennée