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-rw-r--r--include/aout/sun4.h219
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diff --git a/include/aout/sun4.h b/include/aout/sun4.h
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+/* SPARC-specific values for a.out files */
+
+/* Some systems, e.g., AIX, may have defined this in header files already
+ included. */
+#undef TARGET_PAGE_SIZE
+#define TARGET_PAGE_SIZE 0x2000 /* 8K. aka NBPG in <sys/param.h> */
+/* Note that some SPARCs have 4K pages, some 8K, some others. */
+
+#define SEG_SIZE_SPARC TARGET_PAGE_SIZE
+#define SEG_SIZE_SUN3 0x20000 /* Resolution of r/w protection hw */
+
+#define TEXT_START_ADDR TARGET_PAGE_SIZE /* Location 0 is not accessible */
+#define N_HEADER_IN_TEXT(x) 1
+
+/* Non-default definitions of the accessor macros... */
+
+/* Segment size varies on Sun-3 versus Sun-4. */
+
+#define N_SEGSIZE(x) (N_MACHTYPE(x) == M_SPARC? SEG_SIZE_SPARC: \
+ N_MACHTYPE(x) == M_68020? SEG_SIZE_SUN3: \
+ /* Guess? */ TARGET_PAGE_SIZE)
+
+/* Virtual Address of text segment from the a.out file. For OMAGIC,
+ (almost always "unlinked .o's" these days), should be zero.
+ Sun added a kludge so that shared libraries linked ZMAGIC get
+ an address of zero if a_entry (!!!) is lower than the otherwise
+ expected text address. These kludges have gotta go!
+ For linked files, should reflect reality if we know it. */
+
+/* This differs from the version in aout64.h (which we override by defining
+ it here) only for NMAGIC (we return TEXT_START_ADDR+EXEC_BYTES_SIZE;
+ they return 0). */
+
+#define N_TXTADDR(x) \
+ (N_MAGIC(x)==OMAGIC? 0 \
+ : (N_MAGIC(x) == ZMAGIC && (x).a_entry < TEXT_START_ADDR)? 0 \
+ : TEXT_START_ADDR+EXEC_BYTES_SIZE)
+
+/* When a file is linked against a shared library on SunOS 4, the
+ dynamic bit in the exec header is set, and the first symbol in the
+ symbol table is __DYNAMIC. Its value is the address of the
+ following structure. */
+
+struct external_sun4_dynamic
+{
+ /* The version number of the structure. SunOS 4.1.x creates files
+ with version number 3, which is what this structure is based on.
+ According to gdb, version 2 is similar. I believe that version 2
+ used a different type of procedure linkage table, and there may
+ have been other differences. */
+ bfd_byte ld_version[4];
+ /* The virtual address of a 28 byte structure used in debugging.
+ The contents are filled in at run time by ld.so. */
+ bfd_byte ldd[4];
+ /* The virtual address of another structure with information about
+ how to relocate the executable at run time. */
+ bfd_byte ld[4];
+};
+
+/* The size of the debugging structure pointed to by the debugger
+ field of __DYNAMIC. */
+#define EXTERNAL_SUN4_DYNAMIC_DEBUGGER_SIZE (24)
+
+/* The structure pointed to by the linker field of __DYNAMIC. As far
+ as I can tell, most of the addresses in this structure are offsets
+ within the file, but some are actually virtual addresses. */
+
+struct internal_sun4_dynamic_link
+{
+ /* Linked list of loaded objects. This is filled in at runtime by
+ ld.so and probably by dlopen. */
+ unsigned long ld_loaded;
+
+ /* The address of the list of names of shared objects which must be
+ included at runtime. Each entry in the list is 16 bytes: the 4
+ byte address of the string naming the object (e.g., for -lc this
+ is "c"); 4 bytes of flags--the high bit is whether to search for
+ the object using the library path; the 2 byte major version
+ number; the 2 byte minor version number; the 4 byte address of
+ the next entry in the list (zero if this is the last entry). The
+ version numbers seem to only be non-zero when doing library
+ searching. */
+ unsigned long ld_need;
+
+ /* The address of the path to search for the shared objects which
+ must be included. This points to a string in PATH format which
+ is generated from the -L arguments to the linker. According to
+ the man page, ld.so implicitly adds ${LD_LIBRARY_PATH} to the
+ beginning of this string and /lib:/usr/lib:/usr/local/lib to the
+ end. The string is terminated by a null byte. This field is
+ zero if there is no additional path. */
+ unsigned long ld_rules;
+
+ /* The address of the global offset table. This appears to be a
+ virtual address, not a file offset. The first entry in the
+ global offset table seems to be the virtual address of the
+ sun4_dynamic structure (the same value as the __DYNAMIC symbol).
+ The global offset table is used for PIC code to hold the
+ addresses of variables. A dynamically linked file which does not
+ itself contain PIC code has a four byte global offset table. */
+ unsigned long ld_got;
+
+ /* The address of the procedure linkage table. This appears to be a
+ virtual address, not a file offset.
+
+ On a SPARC, the table is composed of 12 byte entries, each of
+ which consists of three instructions. The first entry is
+ sethi %hi(0),%g1
+ jmp %g1
+ nop
+ These instructions are changed by ld.so into a jump directly into
+ ld.so itself. Each subsequent entry is
+ save %sp, -96, %sp
+ call <address of first entry in procedure linkage table>
+ <reloc_number | 0x01000000>
+ The reloc_number is the number of the reloc to use to resolve
+ this entry. The reloc will be a JMP_SLOT reloc against some
+ symbol that is not defined in this object file but should be
+ defined in a shared object (if it is not, ld.so will report a
+ runtime error and exit). The constant 0x010000000 turns the
+ reloc number into a sethi of %g0, which does nothing since %g0 is
+ hardwired to zero.
+
+ When one of these entries is executed, it winds up calling into
+ ld.so. ld.so looks at the reloc number, available via the return
+ address, to determine which entry this is. It then looks at the
+ reloc and patches up the entry in the table into a sethi and jmp
+ to the real address followed by a nop. This means that the reloc
+ lookup only has to happen once, and it also means that the
+ relocation only needs to be done if the function is actually
+ called. The relocation is expensive because ld.so must look up
+ the symbol by name.
+
+ The size of the procedure linkage table is given by the ld_plt_sz
+ field. */
+ unsigned long ld_plt;
+
+ /* The address of the relocs. These are in the same format as
+ ordinary relocs. Symbol index numbers refer to the symbols
+ pointed to by ld_stab. I think the only way to determine the
+ number of relocs is to assume that all the bytes from ld_rel to
+ ld_hash contain reloc entries. */
+ unsigned long ld_rel;
+
+ /* The address of a hash table of symbols. The hash table has
+ roughly the same number of entries as there are dynamic symbols;
+ I think the only way to get the exact size is to assume that
+ every byte from ld_hash to ld_stab is devoted to the hash table.
+
+ Each entry in the hash table is eight bytes. The first four
+ bytes are a symbol index into the dynamic symbols. The second
+ four bytes are the index of the next hash table entry in the
+ bucket. The ld_buckets field gives the number of buckets, say B.
+ The first B entries in the hash table each start a bucket which
+ is chained through the second four bytes of each entry. A value
+ of zero ends the chain.
+
+ The hash function is simply
+ h = 0;
+ while (*string != '\0')
+ h = (h << 1) + *string++;
+ h &= 0x7fffffff;
+
+ To look up a symbol, compute the hash value of the name. Take
+ the modulos of hash value and the number of buckets. Start at
+ that entry in the hash table. See if the symbol (from the first
+ four bytes of the hash table entry) has the name you are looking
+ for. If not, use the chain field (the second four bytes of the
+ hash table entry) to move on to the next entry in this bucket.
+ If the chain field is zero you have reached the end of the
+ bucket, and the symbol is not in the hash table. */
+ unsigned long ld_hash;
+
+ /* The address of the symbol table. This is a list of
+ external_nlist structures. The string indices are relative to
+ the ld_symbols field. I think the only way to determine the
+ number of symbols is to assume that all the bytes between ld_stab
+ and ld_symbols are external_nlist structures. */
+ unsigned long ld_stab;
+
+ /* I don't know what this is for. It seems to always be zero. */
+ unsigned long ld_stab_hash;
+
+ /* The number of buckets in the hash table. */
+ unsigned long ld_buckets;
+
+ /* The address of the symbol string table. The first string in this
+ string table need not be the empty string. */
+ unsigned long ld_symbols;
+
+ /* The size in bytes of the symbol string table. */
+ unsigned long ld_symb_size;
+
+ /* The size in bytes of the text segment. */
+ unsigned long ld_text;
+
+ /* The size in bytes of the procedure linkage table. */
+ unsigned long ld_plt_sz;
+};
+
+/* The external form of the structure. */
+
+struct external_sun4_dynamic_link
+{
+ bfd_byte ld_loaded[4];
+ bfd_byte ld_need[4];
+ bfd_byte ld_rules[4];
+ bfd_byte ld_got[4];
+ bfd_byte ld_plt[4];
+ bfd_byte ld_rel[4];
+ bfd_byte ld_hash[4];
+ bfd_byte ld_stab[4];
+ bfd_byte ld_stab_hash[4];
+ bfd_byte ld_buckets[4];
+ bfd_byte ld_symbols[4];
+ bfd_byte ld_symb_size[4];
+ bfd_byte ld_text[4];
+ bfd_byte ld_plt_sz[4];
+};