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  1. Dec 15, 2020
  2. Sep 18, 2020
  3. Sep 09, 2020
  4. Jul 10, 2020
    • Markus Armbruster's avatar
      error: Eliminate error_propagate() with Coccinelle, part 1 · 668f62ec
      Markus Armbruster authored
      
      When all we do with an Error we receive into a local variable is
      propagating to somewhere else, we can just as well receive it there
      right away.  Convert
      
          if (!foo(..., &err)) {
              ...
              error_propagate(errp, err);
              ...
              return ...
          }
      
      to
      
          if (!foo(..., errp)) {
              ...
              ...
              return ...
          }
      
      where nothing else needs @err.  Coccinelle script:
      
          @rule1 forall@
          identifier fun, err, errp, lbl;
          expression list args, args2;
          binary operator op;
          constant c1, c2;
          symbol false;
          @@
               if (
          (
          -        fun(args, &err, args2)
          +        fun(args, errp, args2)
          |
          -        !fun(args, &err, args2)
          +        !fun(args, errp, args2)
          |
          -        fun(args, &err, args2) op c1
          +        fun(args, errp, args2) op c1
          )
                  )
               {
                   ... when != err
                       when != lbl:
                       when strict
          -        error_propagate(errp, err);
                   ... when != err
          (
                   return;
          |
                   return c2;
          |
                   return false;
          )
               }
      
          @rule2 forall@
          identifier fun, err, errp, lbl;
          expression list args, args2;
          expression var;
          binary operator op;
          constant c1, c2;
          symbol false;
          @@
          -    var = fun(args, &err, args2);
          +    var = fun(args, errp, args2);
               ... when != err
               if (
          (
                   var
          |
                   !var
          |
                   var op c1
          )
                  )
               {
                   ... when != err
                       when != lbl:
                       when strict
          -        error_propagate(errp, err);
                   ... when != err
          (
                   return;
          |
                   return c2;
          |
                   return false;
          |
                   return var;
          )
               }
      
          @depends on rule1 || rule2@
          identifier err;
          @@
          -    Error *err = NULL;
               ... when != err
      
      Not exactly elegant, I'm afraid.
      
      The "when != lbl:" is necessary to avoid transforming
      
               if (fun(args, &err)) {
                   goto out
               }
               ...
           out:
               error_propagate(errp, err);
      
      even though other paths to label out still need the error_propagate().
      For an actual example, see sclp_realize().
      
      Without the "when strict", Coccinelle transforms vfio_msix_setup(),
      incorrectly.  I don't know what exactly "when strict" does, only that
      it helps here.
      
      The match of return is narrower than what I want, but I can't figure
      out how to express "return where the operand doesn't use @err".  For
      an example where it's too narrow, see vfio_intx_enable().
      
      Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
      confused by ARMSSE being used both as typedef and function-like macro
      there.  Converted manually.
      
      Line breaks tidied up manually.  One nested declaration of @local_err
      deleted manually.  Preexisting unwanted blank line dropped in
      hw/riscv/sifive_e.c.
      
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      Reviewed-by: default avatarEric Blake <eblake@redhat.com>
      Message-Id: <20200707160613.848843-35-armbru@redhat.com>
      668f62ec
    • Markus Armbruster's avatar
      error: Avoid unnecessary error_propagate() after error_setg() · dcfe4805
      Markus Armbruster authored
      
      Replace
      
          error_setg(&err, ...);
          error_propagate(errp, err);
      
      by
      
          error_setg(errp, ...);
      
      Related pattern:
      
          if (...) {
              error_setg(&err, ...);
              goto out;
          }
          ...
       out:
          error_propagate(errp, err);
          return;
      
      When all paths to label out are that way, replace by
      
          if (...) {
              error_setg(errp, ...);
              return;
          }
      
      and delete the label along with the error_propagate().
      
      When we have at most one other path that actually needs to propagate,
      and maybe one at the end that where propagation is unnecessary, e.g.
      
          foo(..., &err);
          if (err) {
              goto out;
          }
          ...
          bar(..., &err);
       out:
          error_propagate(errp, err);
          return;
      
      move the error_propagate() to where it's needed, like
      
          if (...) {
              foo(..., &err);
              error_propagate(errp, err);
              return;
          }
          ...
          bar(..., errp);
          return;
      
      and transform the error_setg() as above.
      
      In some places, the transformation results in obviously unnecessary
      error_propagate().  The next few commits will eliminate them.
      
      Bonus: the elimination of gotos will make later patches in this series
      easier to review.
      
      Candidates for conversion tracked down with this Coccinelle script:
      
          @@
          identifier err, errp;
          expression list args;
          @@
          -    error_setg(&err, args);
          +    error_setg(errp, args);
               ... when != err
               error_propagate(errp, err);
      
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      Reviewed-by: default avatarEric Blake <eblake@redhat.com>
      Message-Id: <20200707160613.848843-34-armbru@redhat.com>
      dcfe4805
    • Markus Armbruster's avatar
      qapi: Use returned bool to check for failure, Coccinelle part · 62a35aaa
      Markus Armbruster authored
      
      The previous commit enables conversion of
      
          visit_foo(..., &err);
          if (err) {
              ...
          }
      
      to
      
          if (!visit_foo(..., errp)) {
              ...
          }
      
      for visitor functions that now return true / false on success / error.
      Coccinelle script:
      
          @@
          identifier fun =~ "check_list|input_type_enum|lv_start_struct|lv_type_bool|lv_type_int64|lv_type_str|lv_type_uint64|output_type_enum|parse_type_bool|parse_type_int64|parse_type_null|parse_type_number|parse_type_size|parse_type_str|parse_type_uint64|print_type_bool|print_type_int64|print_type_null|print_type_number|print_type_size|print_type_str|print_type_uint64|qapi_clone_start_alternate|qapi_clone_start_list|qapi_clone_start_struct|qapi_clone_type_bool|qapi_clone_type_int64|qapi_clone_type_null|qapi_clone_type_number|qapi_clone_type_str|qapi_clone_type_uint64|qapi_dealloc_start_list|qapi_dealloc_start_struct|qapi_dealloc_type_anything|qapi_dealloc_type_bool|qapi_dealloc_type_int64|qapi_dealloc_type_null|qapi_dealloc_type_number|qapi_dealloc_type_str|qapi_dealloc_type_uint64|qobject_input_check_list|qobject_input_check_struct|qobject_input_start_alternate|qobject_input_start_list|qobject_input_start_struct|qobject_input_type_any|qobject_input_type_bool|qobject_input_type_bool_keyval|qobject_input_type_int64|qobject_input_type_int64_keyval|qobject_input_type_null|qobject_input_type_number|qobject_input_type_number_keyval|qobject_input_type_size_keyval|qobject_input_type_str|qobject_input_type_str_keyval|qobject_input_type_uint64|qobject_input_type_uint64_keyval|qobject_output_start_list|qobject_output_start_struct|qobject_output_type_any|qobject_output_type_bool|qobject_output_type_int64|qobject_output_type_null|qobject_output_type_number|qobject_output_type_str|qobject_output_type_uint64|start_list|visit_check_list|visit_check_struct|visit_start_alternate|visit_start_list|visit_start_struct|visit_type_.*";
          expression list args;
          typedef Error;
          Error *err;
          @@
          -    fun(args, &err);
          -    if (err)
          +    if (!fun(args, &err))
               {
                   ...
               }
      
      A few line breaks tidied up manually.
      
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      Reviewed-by: default avatarEric Blake <eblake@redhat.com>
      Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
      Message-Id: <20200707160613.848843-19-armbru@redhat.com>
      62a35aaa
  5. May 15, 2020
    • Markus Armbruster's avatar
      qom: Drop parameter @errp of object_property_add() & friends · d2623129
      Markus Armbruster authored
      
      The only way object_property_add() can fail is when a property with
      the same name already exists.  Since our property names are all
      hardcoded, failure is a programming error, and the appropriate way to
      handle it is passing &error_abort.
      
      Same for its variants, except for object_property_add_child(), which
      additionally fails when the child already has a parent.  Parentage is
      also under program control, so this is a programming error, too.
      
      We have a bit over 500 callers.  Almost half of them pass
      &error_abort, slightly fewer ignore errors, one test case handles
      errors, and the remaining few callers pass them to their own callers.
      
      The previous few commits demonstrated once again that ignoring
      programming errors is a bad idea.
      
      Of the few ones that pass on errors, several violate the Error API.
      The Error ** argument must be NULL, &error_abort, &error_fatal, or a
      pointer to a variable containing NULL.  Passing an argument of the
      latter kind twice without clearing it in between is wrong: if the
      first call sets an error, it no longer points to NULL for the second
      call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
      sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
      are wrong that way.
      
      When the one appropriate choice of argument is &error_abort, letting
      users pick the argument is a bad idea.
      
      Drop parameter @errp and assert the preconditions instead.
      
      There's one exception to "duplicate property name is a programming
      error": the way object_property_add() implements the magic (and
      undocumented) "automatic arrayification".  Don't drop @errp there.
      Instead, rename object_property_add() to object_property_try_add(),
      and add the obvious wrapper object_property_add().
      
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      Reviewed-by: default avatarEric Blake <eblake@redhat.com>
      Reviewed-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      Message-Id: <20200505152926.18877-15-armbru@redhat.com>
      [Two semantic rebase conflicts resolved]
      d2623129
  6. Mar 31, 2020
  7. Jun 12, 2019
    • Markus Armbruster's avatar
      Include qemu-common.h exactly where needed · a8d25326
      Markus Armbruster authored
      
      No header includes qemu-common.h after this commit, as prescribed by
      qemu-common.h's file comment.
      
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      Message-Id: <20190523143508.25387-5-armbru@redhat.com>
      [Rebased with conflicts resolved automatically, except for
      include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
      block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
      target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
      target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
      target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
      target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
      net/tap-bsd.c fixed up]
      a8d25326
  8. Mar 02, 2018
  9. Jun 20, 2017
  10. Mar 22, 2016
    • Markus Armbruster's avatar
      include/qemu/osdep.h: Don't include qapi/error.h · da34e65c
      Markus Armbruster authored
      
      Commit 57cb38b3 included qapi/error.h into qemu/osdep.h to get the
      Error typedef.  Since then, we've moved to include qemu/osdep.h
      everywhere.  Its file comment explains: "To avoid getting into
      possible circular include dependencies, this file should not include
      any other QEMU headers, with the exceptions of config-host.h,
      compiler.h, os-posix.h and os-win32.h, all of which are doing a
      similar job to this file and are under similar constraints."
      qapi/error.h doesn't do a similar job, and it doesn't adhere to
      similar constraints: it includes qapi-types.h.  That's in excess of
      100KiB of crap most .c files don't actually need.
      
      Add the typedef to qemu/typedefs.h, and include that instead of
      qapi/error.h.  Include qapi/error.h in .c files that need it and don't
      get it now.  Include qapi-types.h in qom/object.h for uint16List.
      
      Update scripts/clean-includes accordingly.  Update it further to match
      reality: replace config.h by config-target.h, add sysemu/os-posix.h,
      sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
      comment quoted above similarly.
      
      This reduces the number of objects depending on qapi/error.h from "all
      of them" to less than a third.  Unfortunately, the number depending on
      qapi-types.h shrinks only a little.  More work is needed for that one.
      
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      [Fix compilation without the spice devel packages. - Paolo]
      Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
      da34e65c
  11. Mar 08, 2016
  12. Feb 08, 2016
    • Eric Blake's avatar
      qom: Swap 'name' next to visitor in ObjectPropertyAccessor · d7bce999
      Eric Blake authored
      
      Similar to the previous patch, it's nice to have all functions
      in the tree that involve a visitor and a name for conversion to
      or from QAPI to consistently stick the 'name' parameter next
      to the Visitor parameter.
      
      Done by manually changing include/qom/object.h and qom/object.c,
      then running this Coccinelle script and touching up the fallout
      (Coccinelle insisted on adding some trailing whitespace).
      
          @ rule1 @
          identifier fn;
          typedef Object, Visitor, Error;
          identifier obj, v, opaque, name, errp;
          @@
           void fn
          - (Object *obj, Visitor *v, void *opaque, const char *name,
          + (Object *obj, Visitor *v, const char *name, void *opaque,
             Error **errp) { ... }
      
          @@
          identifier rule1.fn;
          expression obj, v, opaque, name, errp;
          @@
           fn(obj, v,
          -   opaque, name,
          +   name, opaque,
              errp)
      
      Signed-off-by: default avatarEric Blake <eblake@redhat.com>
      Reviewed-by: default avatarMarc-André Lureau <marcandre.lureau@redhat.com>
      Message-Id: <1454075341-13658-20-git-send-email-eblake@redhat.com>
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      d7bce999
    • Eric Blake's avatar
      qapi: Swap visit_* arguments for consistent 'name' placement · 51e72bc1
      Eric Blake authored
      
      JSON uses "name":value, but many of our visitor interfaces were
      called with visit_type_FOO(v, &value, name, errp).  This can be
      a bit confusing to have to mentally swap the parameter order to
      match JSON order.  It's particularly bad for visit_start_struct(),
      where the 'name' parameter is smack in the middle of the
      otherwise-related group of 'obj, kind, size' parameters! It's
      time to do a global swap of the parameter ordering, so that the
      'name' parameter is always immediately after the Visitor argument.
      
      Additional reason in favor of the swap: the existing include/qjson.h
      prefers listing 'name' first in json_prop_*(), and I have plans to
      unify that file with the qapi visitors; listing 'name' first in
      qapi will minimize churn to the (admittedly few) qjson.h clients.
      
      Later patches will then fix docs, object.h, visitor-impl.h, and
      those clients to match.
      
      Done by first patching scripts/qapi*.py by hand to make generated
      files do what I want, then by running the following Coccinelle
      script to affect the rest of the code base:
       $ spatch --sp-file script `git grep -l '\bvisit_' -- '**/*.[ch]'`
      I then had to apply some touchups (Coccinelle insisted on TAB
      indentation in visitor.h, and botched the signature of
      visit_type_enum() by rewriting 'const char *const strings[]' to
      the syntactically invalid 'const char*const[] strings').  The
      movement of parameters is sufficient to provoke compiler errors
      if any callers were missed.
      
          // Part 1: Swap declaration order
          @@
          type TV, TErr, TObj, T1, T2;
          identifier OBJ, ARG1, ARG2;
          @@
           void visit_start_struct
          -(TV v, TObj OBJ, T1 ARG1, const char *name, T2 ARG2, TErr errp)
          +(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
           { ... }
      
          @@
          type bool, TV, T1;
          identifier ARG1;
          @@
           bool visit_optional
          -(TV v, T1 ARG1, const char *name)
          +(TV v, const char *name, T1 ARG1)
           { ... }
      
          @@
          type TV, TErr, TObj, T1;
          identifier OBJ, ARG1;
          @@
           void visit_get_next_type
          -(TV v, TObj OBJ, T1 ARG1, const char *name, TErr errp)
          +(TV v, const char *name, TObj OBJ, T1 ARG1, TErr errp)
           { ... }
      
          @@
          type TV, TErr, TObj, T1, T2;
          identifier OBJ, ARG1, ARG2;
          @@
           void visit_type_enum
          -(TV v, TObj OBJ, T1 ARG1, T2 ARG2, const char *name, TErr errp)
          +(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
           { ... }
      
          @@
          type TV, TErr, TObj;
          identifier OBJ;
          identifier VISIT_TYPE =~ "^visit_type_";
          @@
           void VISIT_TYPE
          -(TV v, TObj OBJ, const char *name, TErr errp)
          +(TV v, const char *name, TObj OBJ, TErr errp)
           { ... }
      
          // Part 2: swap caller order
          @@
          expression V, NAME, OBJ, ARG1, ARG2, ERR;
          identifier VISIT_TYPE =~ "^visit_type_";
          @@
          (
          -visit_start_struct(V, OBJ, ARG1, NAME, ARG2, ERR)
          +visit_start_struct(V, NAME, OBJ, ARG1, ARG2, ERR)
          |
          -visit_optional(V, ARG1, NAME)
          +visit_optional(V, NAME, ARG1)
          |
          -visit_get_next_type(V, OBJ, ARG1, NAME, ERR)
          +visit_get_next_type(V, NAME, OBJ, ARG1, ERR)
          |
          -visit_type_enum(V, OBJ, ARG1, ARG2, NAME, ERR)
          +visit_type_enum(V, NAME, OBJ, ARG1, ARG2, ERR)
          |
          -VISIT_TYPE(V, OBJ, NAME, ERR)
          +VISIT_TYPE(V, NAME, OBJ, ERR)
          )
      
      Signed-off-by: default avatarEric Blake <eblake@redhat.com>
      Reviewed-by: default avatarMarc-André Lureau <marcandre.lureau@redhat.com>
      Message-Id: <1454075341-13658-19-git-send-email-eblake@redhat.com>
      Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
      51e72bc1
  13. Feb 04, 2016
    • Peter Maydell's avatar
      net: Clean up includes · 2744d920
      Peter Maydell authored
      
      Clean up includes so that osdep.h is included first and headers
      which it implies are not included manually.
      
      This commit was created with scripts/clean-includes.
      
      Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
      Message-id: 1454089805-5470-11-git-send-email-peter.maydell@linaro.org
      2744d920
  14. Oct 12, 2015
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