From: Matthias Bolte Date: Fri, 12 Nov 2010 14:33:00 +0000 (+0100) Subject: docs: Prepare hacking.html.in to generate HACKING from it X-Git-Tag: v0.8.6~107 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d39620e36770c8baeacff74152a812208fbc70f5;p=thirdparty%2Flibvirt.git docs: Prepare hacking.html.in to generate HACKING from it Tweak pre tags to achieve proper indentation of their plaintext representation. Also use more b/i/code tags. --- diff --git a/docs/hacking.html.in b/docs/hacking.html.in index bd8b443a94..47849c51ee 100644 --- a/docs/hacking.html.in +++ b/docs/hacking.html.in @@ -5,20 +5,21 @@

General tips for contributing patches

-
  1. Discuss any large changes on the mailing list first. Post patches early and listen to feedback.

  2. Post patches in unified diff format. A command similar to this should work:

    - 
    -  diff -urp libvirt.orig/ libvirt.modified/ > libvirt-myfeature.patch
    +
    +  diff -urp libvirt.orig/ libvirt.modified/ > libvirt-myfeature.patch
+

    or:

    - 
    -  git diff > libvirt-myfeature.patch
    +
    +  git diff > libvirt-myfeature.patch
+
  3. Split large changes into a series of smaller patches, self-contained if possible, with an explanation of each patch and an explanation of how @@ -27,35 +28,39 @@ only follow GIT and don't care much about released versions.

  4. Run the automated tests on your code before submitting any changes. In particular, configure with compile warnings set to -Werror:

    - 
    -  ./configure --enable-compile-warnings=error
    +
    +  ./configure --enable-compile-warnings=error
+

    and run the tests:

    - 
    +
       make check
   make syntax-check
-  make -C tests valgrind
    
+  make -C tests valgrind
+

    The latter test checks for memory leaks.

    -

    - If you encounter any failing tests, the VIR_TEST_DEBUG - environment variable may provide extra information to debug - the failures. Larger values of VIR_TEST_DEBUG may provide - larger amounts of information: -

    +

    + If you encounter any failing tests, the VIR_TEST_DEBUG + environment variable may provide extra information to debug + the failures. Larger values of VIR_TEST_DEBUG may provide + larger amounts of information: +

    - 
    +
       VIR_TEST_DEBUG=1 make check    (or)
-  VIR_TEST_DEBUG=2 make check
    
-	
    
-	  Also, individual tests can be run from inside the 'tests/'
-	  directory, like:
-	
    
-	
    -  ./qemuxml2xmltest
    
+  VIR_TEST_DEBUG=2 make check
+
    +

    + Also, individual tests can be run from inside the tests/ + directory, like: +

    +
    +  ./qemuxml2xmltest
+
  5. Update tests and/or documentation, particularly if you are adding @@ -82,7 +87,7 @@ If you use Emacs, add the following to one of one of your start-up files (e.g., ~/.emacs), to help ensure that you get indentation right:

    - 
    +
       ;;; When editing C sources in libvirt, use this style.
   (defun libvirt-c-mode ()
     "C mode with adjusted defaults for use with libvirt."
@@ -105,7 +110,7 @@
       around operators and keywords:
     
    
 
-    
    +
       indent-libvirt()
   {
     indent -bad -bap -bbb -bli4 -br -ce -brs -cs -i4 -l75 -lc75 \
@@ -116,7 +121,7 @@
 
     
    
       Note that sometimes you'll have to post-process that output further, by
-      piping it through "expand -i", since some leading TABs can get through.
+      piping it through expand -i, since some leading TABs can get through.
       Usually they're in macro definitions or strings, and should be converted
       anyhow.
     
    
@@ -125,18 +130,20 @@
     
    Curly braces
    
 
     
    
-      Omit the curly braces around an "if", "while", "for" etc. body only
+      Omit the curly braces around an if, while,
+      for etc. body only
       when that body occupies a single line.  In every other case we require
       the braces.  This ensures that it is trivially easy to identify a
-      single-*statement* loop: each has only one *line* in its body.
+      single-statement loop: each has only one line in its body.
     
    
     
    
       Omitting braces with a single-line body is fine:
     
    
 
-    
    +
       while (expr) // one-line body -> omitting curly braces is ok
-      single_line_stmt ();
    
+      single_line_stmt();
+
    
 
     
    
       However, the moment your loop/if/else body extends onto a second
@@ -146,26 +153,29 @@
       it is already a multi-statement loop:
     
    
 
-    
    +
       while (true) // BAD! multi-line body with no braces
       /* comment... */
-      single_line_stmt ();
    
+      single_line_stmt();
+
    
     
    
       Do this instead:
     
    
-    
    +
       while (true) { // Always put braces around a multi-line body.
       /* comment... */
-      single_line_stmt ();
-  }
    
+      single_line_stmt();
+  }
+
    
     
    
       There is one exception: when the second body line is not at the same
       indentation level as the first body line:
     
    
-    
    +
       if (expr)
-      die ("a diagnostic that would make this line"
-           " extend past the 80-column limit"));
    
+      die("a diagnostic that would make this line"
+          " extend past the 80-column limit"));
+
    
 
     
    
       It is safe to omit the braces in the code above, since the
@@ -177,40 +187,44 @@
       To reiterate, don't do this:
     
    
 
-    
    +
       if (expr)            // BAD: no braces around...
       while (expr_2) { // ... a multi-line body
           ...
-      }
    
+      }
+
    
 
     
    
       Do this, instead:
     
    
 
-    
    +
       if (expr) {
       while (expr_2) {
           ...
       }
-  }
    
+  }
+
    
 
     
    
       However, there is one exception in the other direction, when even a
       one-line block should have braces.  That occurs when that one-line,
-      brace-less block is an "else" block, and the corresponding "then" block
-      *does* use braces.  In that case, either put braces around the "else"
-      block, or negate the "if"-condition and swap the bodies, putting the
+      brace-less block is an else block, and the corresponding
+      then block does use braces.  In that case, either
+      put braces around the else block, or negate the
+      if-condition and swap the bodies, putting the
       one-line block first and making the longer, multi-line block be the
-      "else" block.
+      else block.
     
    
 
-    
    +
       if (expr) {
       ...
       ...
   }
   else
-      x = y;    // BAD: braceless "else" with braced "then"
    
+      x = y;    // BAD: braceless "else" with braced "then"
+
    
 
     
    
       This is preferred, especially when the multi-line body is more than a
@@ -219,43 +233,45 @@
       after the more involved block:
     
    
 
-    
    +
       if (!expr)
     x = y; // putting the smaller block first is more readable
   else {
       ...
       ...
-  }
    
+  }
+
    
 
     
    
       If you'd rather not negate the condition, then at least add braces:
     
    
 
-    
    +
       if (expr) {
       ...
       ...
   } else {
       x = y;
-  }
    
+  }
+
    
 
     
    Preprocessor
    
 
     
    
       For variadic macros, stick with C99 syntax:
     
    
-  
    +
       #define vshPrint(_ctl, ...) fprintf(stdout, __VA_ARGS__)
-  
    
+
    
 
     
    Use parenthesis when checking if a macro is defined, and use
     indentation to track nesting:
     
    
-  
    +
       #if defined(HAVE_POSIX_FALLOCATE) && !defined(HAVE_FALLOCATE)
   # define fallocate(a,ignored,b,c) posix_fallocate(a,b,c)
   #endif
-  
    
+
    
 
     
    C types
    
 
@@ -266,45 +282,51 @@
     
    Scalars
    
 
     
      
-      
    • If you're using "int" or "long", odds are good that there's a better type.
      • 
+      
    • If you're using int or long, odds are
+          good that there's a better type.
      • 
       
    • If a variable is counting something, be sure to declare it with an
         unsigned type.
      • 
-      
    • If it's memory-size-related, use size_t (use ssize_t only if required).
      • 
-      
    • If it's file-size related, use uintmax_t, or maybe off_t.
      • 
-      
    • If it's file-offset related (i.e., signed), use off_t.
      • 
-      
    • If it's just counting small numbers use "unsigned int";
+      
    • If it's memory-size-related, use size_t (use
+        ssize_t only if required).
      • 
+      
    • If it's file-size related, use uintmax_t, or maybe off_t.
      • 
+      
    • If it's file-offset related (i.e., signed), use off_t.
      • 
+      
    • If it's just counting small numbers use unsigned int;
         (on all but oddball embedded systems, you can assume that that
         type is at least four bytes wide).
      • 
-      
    • If a variable has boolean semantics, give it the "bool" type
-        and use the corresponding "true" and "false" macros.  It's ok
-        to include <stdbool.h>, since libvirt's use of gnulib ensures
+      
    • If a variable has boolean semantics, give it the bool type
+        and use the corresponding true and false macros.
+         It's ok to include <stdbool.h>, since libvirt's use of gnulib ensures
           that it exists and is usable.
      • 
       
    • In the unusual event that you require a specific width, use a
-        standard type like int32_t, uint32_t, uint64_t, etc.
      • 
-      
    • While using "bool" is good for readability, it comes with minor caveats:
+        standard type like int32_t, uint32_t,
+        uint64_t, etc.
      • 
+      
    • While using bool is good for readability, it comes with
+          minor caveats:
         
        
-          
      • Don't use "bool" in places where the type size must be constant across
+          
      • Don't use bool in places where the type size must be constant across
             all systems, like public interfaces and on-the-wire protocols.  Note
-            that it would be possible (albeit wasteful) to use "bool" in libvirt's
-            logical wire protocol, since XDR maps that to its lower-level bool_t
-            type, which *is* fixed-size.
        • 
-          
      • Don't compare a bool variable against the literal, "true",
-            since a value with a logical non-false value need not be "1".
-            I.e., don't write "if (seen == true) ...".  Rather, write "if (seen)...".
        • 
+            that it would be possible (albeit wasteful) to use bool in libvirt's
+            logical wire protocol, since XDR maps that to its lower-level bool_t
+            type, which is fixed-size.
+          
      • Don't compare a bool variable against the literal, true,
+            since a value with a logical non-false value need not be 1.
+            I.e., don't write if (seen == true) ....  Rather,
+            write if (seen)....
        • 
         
      
       
      • 
     
    
 
     
    
       Of course, take all of the above with a grain of salt.  If you're about
-      to use some system interface that requires a type like size_t, pid_t or
-      off_t, use matching types for any corresponding variables.
+      to use some system interface that requires a type like size_t,
+      pid_t or off_t, use matching types for any
+      corresponding variables.
     
    
 
     
    
-      Also, if you try to use e.g., "unsigned int" as a type, and that
+      Also, if you try to use e.g., unsigned int as a type, and that
       conflicts with the signedness of a related variable, sometimes
-      it's best just to use the *wrong* type, if "pulling the thread"
+      it's best just to use the wrong type, if pulling the thread
       and fixing all related variables would be too invasive.
     
    
 
@@ -317,9 +339,9 @@
     
    Pointers
    
 
     
    
-      Ensure that all of your pointers are "const-correct".
+      Ensure that all of your pointers are const-correct.
       Unless a pointer is used to modify the pointed-to storage,
-      give it the "const" attribute.  That way, the reader knows
+      give it the const attribute.  That way, the reader knows
       up-front that this is a read-only pointer.  Perhaps more
       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
@@ -336,57 +358,57 @@
     
    
 
     
      
-      
    • eg to allocate  a single object:
      
-
+      
    • e.g. to allocate  a single object:
      
 
      -      virDomainPtr domain;
+  virDomainPtr domain;
 
-      if (VIR_ALLOC(domain) < 0) {
-          virReportOOMError();
-          return NULL;
-      }
-
      • 
-
-      
    • eg to allocate an array of objects
      
+  if (VIR_ALLOC(domain) < 0) {
+      virReportOOMError();
+      return NULL;
+  }
+
    
+
    6. +

  6. e.g. to allocate an array of objects

    -       virDomainPtr domains;
-       int ndomains = 10;
-
-       if (VIR_ALLOC_N(domains, ndomains) < 0) {
-           virReportOOMError();
-           return NULL;
-       }
-
    7. + virDomainPtr domains; + int ndomains = 10; -

  7. eg to allocate an array of object pointers

    + if (VIR_ALLOC_N(domains, ndomains) < 0) { + virReportOOMError(); + return NULL; + } + +
    8. +

  8. e.g. to allocate an array of object pointers

    -       virDomainPtr *domains;
-       int ndomains = 10;
+  virDomainPtr *domains;
+  int ndomains = 10;
 
-       if (VIR_ALLOC_N(domains, ndomains) < 0) {
-           virReportOOMError();
-           return NULL;
-       }
-
    9. - -

  9. eg to re-allocate the array of domains to be longer

    + if (VIR_ALLOC_N(domains, ndomains) < 0) { + virReportOOMError(); + return NULL; + } + +
    10. +

  10. e.g. to re-allocate the array of domains to be longer

    -       ndomains = 20
-
-       if (VIR_REALLOC_N(domains, ndomains) < 0) {
-           virReportOOMError();
-           return NULL;
-       }
-
    11. + ndomains = 20 -

  11. eg to free the domain

    + if (VIR_REALLOC_N(domains, ndomains) < 0) { + virReportOOMError(); + return NULL; + } + +
    12. +

  12. e.g. to free the domain

    -       VIR_FREE(domain);
-
    13. + VIR_FREE(domain); + +

    File handling

    @@ -398,20 +420,21 @@

    String comparisons

    @@ -423,39 +446,36 @@ @@ -469,7 +489,10 @@ it extremely dangerous to use. Instead, use one of the functionally equivalent functions:

    - 
    virStrncpy(char *dest, const char *src, size_t n, size_t destbytes)
    + +
    +  virStrncpy(char *dest, const char *src, size_t n, size_t destbytes)
+

    The first three arguments have the same meaning as for strncpy; namely the destination, source, and number of bytes to copy, @@ -481,8 +504,9 @@ trailing \0 is appended.

    - 
    virStrcpy(char *dest, const char *src, size_t destbytes)
    - +
    +  virStrcpy(char *dest, const char *src, size_t destbytes)
+

    Use this variant if you know you want to copy the entire src string into dest. Note that this is a macro, so arguments could @@ -490,11 +514,12 @@ virStrncpy(dest, src, strlen(src), destbytes)

    - 
    virStrcpyStatic(char *dest, const char *src)
    - +
    +  virStrcpyStatic(char *dest, const char *src)
+

    Use this variant if you know you want to copy the entire src - string into dest *and* you know that your destination string is + string into dest and you know that your destination string is a static string (i.e. that sizeof(dest) returns something meaningful). Note that this is a macro, so arguments could be evaluated more than once. This is equivalent to @@ -511,9 +536,10 @@

    eg typical usage is as follows:

    - 
    +
       char *
-  somefunction(...) {
+  somefunction(...)
+  {
      virBuffer buf = VIR_BUFFER_INITIALIZER;
 
      ...
@@ -545,7 +571,7 @@
       *.c source files:
     
    
 
-    
    +
       /*
    * Copyright notice
    * ....
@@ -561,7 +587,7 @@
   #include <limits.h>
 
   #if HAVE_NUMACTL                Some system includes aren't supported
-  # include <numa.h>               everywhere so need these #if guards.
+  # include <numa.h>              everywhere so need these #if guards.
   #endif
 
   #include "internal.h"           Include this first, after system includes.
@@ -569,13 +595,14 @@
   #include "util.h"               Any libvirt internal header files.
   #include "buf.h"
 
-  static myInternalFunc ()        The actual code.
+  static int
+  myInternalFunc()                The actual code.
   {
-    ...
+      ...
 
    
 
     
    
-      Of particular note: *DO NOT* include libvirt/libvirt.h or
+      Of particular note: Do not include libvirt/libvirt.h or
       libvirt/virterror.h.  It is included by "internal.h" already and there
       are some special reasons why you cannot include these files
       explicitly.
@@ -591,9 +618,9 @@
       the one for virAsprintf, in util.h:
     
    
 
-    
    -    int virAsprintf(char **strp, const char *fmt, ...)
-        ATTRIBUTE_FORMAT(printf, 2, 3);
+
    +  int virAsprintf(char **strp, const char *fmt, ...)
+      ATTRIBUTE_FORMAT(printf, 2, 3);
 
    
 
     
    
@@ -654,7 +681,7 @@
       Although libvirt does not encourage the Linux kernel wind/unwind
       style of multiple labels, there's a good general discussion of
       the issue archived at
-      KernelTrap
+      KernelTrap
     
    
 
     
    
@@ -662,11 +689,12 @@
       makes sense:
     
    
 
-    
    +
           error: A path only taken upon return with an error code
     cleanup: A path taken upon return with success code + optional error
   no_memory: A path only taken upon return with an OOM error code
-      retry: If needing to jump upwards (eg retry on EINTR)
    
+      retry: If needing to jump upwards (eg retry on EINTR)
+
    
 
 
 
@@ -691,7 +719,7 @@
       configure with
     
    
 
    -      --enable-compile-warnings=error
+  --enable-compile-warnings=error
 
    
     
    
       which adds -Werror to compile flags, so no warnings get missed