Re: [Qemu-devel] [PULL for-1.7 v2 4/6] acpi-build: fix build on glib < 2.14

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Nov 25, 2013 at 09:14:19PM +0100, Erik Rull wrote:
> Michael S. Tsirkin wrote:
> >g_array_get_element_size was only added in glib 2.14,
> >there's no way to find element size in with an older glib.
> >
> >Fortunately we only use a single table (linker) where element size > 1.
> >Switch element size to 1 everywhere, then we can just look at len field
> >to get table size in bytes.
> >
> >Add an assert to make sure we catch any violations of this rule.
> >
> >Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> >Reported-by: Richard Henderson <rth@redhat.com>
> >Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> >---
> >  hw/i386/acpi-build.c         | 5 ++++-
> >  hw/i386/bios-linker-loader.c | 8 ++++----
> >  2 files changed, 8 insertions(+), 5 deletions(-)
> >
> >diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> >index 59a17df..5f36e7e 100644
> >--- a/hw/i386/acpi-build.c
> >+++ b/hw/i386/acpi-build.c
> >@@ -425,7 +425,10 @@ static inline void *acpi_data_push(GArray *table_data, unsigned size)
> >
> >  static unsigned acpi_data_len(GArray *table)
> >  {
> >-    return table->len * g_array_get_element_size(table);
> >+#if GLIB_CHECK_VERSION(2, 14, 0)
> >+    assert(g_array_get_element_size(table) == 1);
> >+#endif
> >+    return table->len;
> >  }
> >
> >  static void acpi_align_size(GArray *blob, unsigned align)
> >diff --git a/hw/i386/bios-linker-loader.c b/hw/i386/bios-linker-loader.c
> >index 0833853..fd23611 100644
> >--- a/hw/i386/bios-linker-loader.c
> >+++ b/hw/i386/bios-linker-loader.c
> >@@ -90,7 +90,7 @@ enum {
> >
> >  GArray *bios_linker_loader_init(void)
> >  {
> >-    return g_array_new(false, true /* clear */, sizeof(BiosLinkerLoaderEntry));
> >+    return g_array_new(false, true /* clear */, 1);
> >  }
> >
> >  /* Free linker wrapper and return the linker array. */
> >@@ -115,7 +115,7 @@ void bios_linker_loader_alloc(GArray *linker,
> >                                      BIOS_LINKER_LOADER_ALLOC_ZONE_HIGH);
> >
> >      /* Alloc entries must come first, so prepend them */
> >-    g_array_prepend_val(linker, entry);
> >+    g_array_prepend_vals(linker, &entry, sizeof entry);
> >  }
> >
> >  void bios_linker_loader_add_checksum(GArray *linker, const char *file,
> >@@ -132,7 +132,7 @@ void bios_linker_loader_add_checksum(GArray *linker, const char *file,
> >      entry.cksum.start = cpu_to_le32((uint8_t *)start - (uint8_t *)table);
> >      entry.cksum.length = cpu_to_le32(size);
> >
> >-    g_array_append_val(linker, entry);
> >+    g_array_append_vals(linker, &entry, sizeof entry);
> >  }
> >
> >  void bios_linker_loader_add_pointer(GArray *linker,
> >@@ -154,5 +154,5 @@ void bios_linker_loader_add_pointer(GArray *linker,
> >      assert(pointer_size == 1 || pointer_size == 2 ||
> >             pointer_size == 4 || pointer_size == 8);
> >
> >-    g_array_append_val(linker, entry);
> >+    g_array_append_vals(linker, &entry, sizeof entry);
> >  }
> >
> 
> Hi all,
> 
> acpi-build.c has another occurence of g_array_get_element_size in
> acpi_align_size. Please put another ifdef for the older glib here,
> too.
> 
> Thanks.
> 
> Best regards,
> 
> Erik
> 


Can you confirm this works?


diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 5f36e7e..1f22fb6 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -425,7 +425,7 @@ static inline void *acpi_data_push(GArray *table_data, unsigned size)
 
 static unsigned acpi_data_len(GArray *table)
 {
-#if GLIB_CHECK_VERSION(2, 14, 0)
+#if GLIB_CHECK_VERSION(2, 22, 0)
     assert(g_array_get_element_size(table) == 1);
 #endif
     return table->len;
@@ -436,9 +436,7 @@ static void acpi_align_size(GArray *blob, unsigned align)
     /* Align size to multiple of given size. This reduces the chance
      * we need to change size in the future (breaking cross version migration).
      */
-    g_array_set_size(blob, (ROUND_UP(acpi_data_len(blob), align) +
-                            g_array_get_element_size(blob) - 1) /
-                             g_array_get_element_size(blob));
+    g_array_set_size(blob, ROUND_UP(acpi_data_len(blob), align));
 }
 
 /* Get pointer within table in a safe manner */