 2562755ee7
			
		
	
	
		2562755ee7
		
	
	
	
	
		
			
			The point of writing a macro embedded in a 'do { ... } while (0)'
loop (particularly if the macro has multiple statements or would
otherwise end with an 'if' statement) is so that the macro can be
used as a drop-in statement with the caller supplying the
trailing ';'.  Although our coding style frowns on brace-less 'if':
  if (cond)
    statement;
  else
    something else;
that is the classic case where failure to use do/while(0) wrapping
would cause the 'else' to pair with any embedded 'if' in the macro
rather than the intended outer 'if'.  But conversely, if the macro
includes an embedded ';', then the same brace-less coding style
would now have two statements, making the 'else' a syntax error
rather than pairing with the outer 'if'.  Thus, even though our
coding style with required braces is not impacted, ending a macro
with ';' makes our code harder to port to projects that use
brace-less styles.
The change should have no semantic impact.  I was not able to
fully compile-test all of the changes (as some of them are
examples of the ugly bit-rotting debug print statements that are
completely elided by default, and I didn't want to recompile
with the necessary -D witnesses - cleaning those up is left as a
bite-sized task for another day); I did, however, audit that for
all files touched, all callers of the changed macros DID supply
a trailing ';' at the callsite, and did not appear to be used
as part of a brace-less conditional.
Found mechanically via: $ git grep -B1 'while (0);' | grep -A1 \\\\
Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20171201232433.25193-7-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
		
	
			
		
			
				
	
	
		
			88 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Utilities for working with ACPI tables
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|  *
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|  * Copyright (c) 2013 Red Hat Inc.
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|  *
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|  * Authors:
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|  *  Michael S. Tsirkin <mst@redhat.com>,
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|  *
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|  * This work is licensed under the terms of the GNU GPL, version 2 or later.
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|  * See the COPYING file in the top-level directory.
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|  */
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| 
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| #ifndef TEST_ACPI_UTILS_H
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| #define TEST_ACPI_UTILS_H
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| 
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| #include "hw/acpi/acpi-defs.h"
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| #include "libqtest.h"
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| 
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| /* DSDT and SSDTs format */
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| typedef struct {
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|     AcpiTableHeader header;
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|     gchar *aml;            /* aml bytecode from guest */
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|     gsize aml_len;
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|     gchar *aml_file;
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|     gchar *asl;            /* asl code generated from aml */
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|     gsize asl_len;
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|     gchar *asl_file;
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|     bool tmp_files_retain;   /* do not delete the temp asl/aml */
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| } AcpiSdtTable;
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| 
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| #define ACPI_READ_FIELD(field, addr)            \
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|     do {                                        \
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|         memread(addr, &field, sizeof(field));   \
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|         addr += sizeof(field);                  \
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|     } while (0)
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| 
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| #define ACPI_READ_ARRAY_PTR(arr, length, addr)  \
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|     do {                                        \
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|         int idx;                                \
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|         for (idx = 0; idx < length; ++idx) {    \
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|             ACPI_READ_FIELD(arr[idx], addr);    \
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|         }                                       \
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|     } while (0)
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| 
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| #define ACPI_READ_ARRAY(arr, addr)                               \
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|     ACPI_READ_ARRAY_PTR(arr, sizeof(arr) / sizeof(arr[0]), addr)
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| 
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| #define ACPI_READ_TABLE_HEADER(table, addr)                      \
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|     do {                                                         \
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|         ACPI_READ_FIELD((table)->signature, addr);               \
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|         ACPI_READ_FIELD((table)->length, addr);                  \
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|         ACPI_READ_FIELD((table)->revision, addr);                \
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|         ACPI_READ_FIELD((table)->checksum, addr);                \
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|         ACPI_READ_ARRAY((table)->oem_id, addr);                  \
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|         ACPI_READ_ARRAY((table)->oem_table_id, addr);            \
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|         ACPI_READ_FIELD((table)->oem_revision, addr);            \
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|         ACPI_READ_ARRAY((table)->asl_compiler_id, addr);         \
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|         ACPI_READ_FIELD((table)->asl_compiler_revision, addr);   \
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|     } while (0)
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| 
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| #define ACPI_ASSERT_CMP(actual, expected) do { \
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|     char ACPI_ASSERT_CMP_str[5] = {}; \
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|     memcpy(ACPI_ASSERT_CMP_str, &actual, 4); \
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|     g_assert_cmpstr(ACPI_ASSERT_CMP_str, ==, expected); \
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| } while (0)
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| 
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| #define ACPI_ASSERT_CMP64(actual, expected) do { \
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|     char ACPI_ASSERT_CMP_str[9] = {}; \
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|     memcpy(ACPI_ASSERT_CMP_str, &actual, 8); \
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|     g_assert_cmpstr(ACPI_ASSERT_CMP_str, ==, expected); \
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| } while (0)
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| 
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| #define ACPI_READ_GENERIC_ADDRESS(field, addr)       \
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|     do {                                             \
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|         ACPI_READ_FIELD((field).space_id, addr);     \
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|         ACPI_READ_FIELD((field).bit_width, addr);    \
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|         ACPI_READ_FIELD((field).bit_offset, addr);   \
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|         ACPI_READ_FIELD((field).access_width, addr); \
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|         ACPI_READ_FIELD((field).address, addr);      \
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|     } while (0)
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| 
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| 
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| uint8_t acpi_calc_checksum(const uint8_t *data, int len);
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| uint32_t acpi_find_rsdp_address(void);
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| void acpi_parse_rsdp_table(uint32_t addr, AcpiRsdpDescriptor *rsdp_table);
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| 
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| #endif  /* TEST_ACPI_UTILS_H */
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