Multiple sections of a given type are combined, and any holes between

sections are filled with zeroes.

This changes the definition of `text', `data', and `bss' to use the
flags set by BFD, rather than requiring hardwired input section names
(for the normal case where one is using GNU ld and the elf2flt.ld linker
script, this should produce identical results, as that only ever
produces the three well-defined sections anyway).

Patch from Miles Bader <miles@gnu.org>.

diff --git a/elf2flt.c b/elf2flt.c
index f1d8489f0af80fbab3374a316e10b0128e751867..f0ee6f1d2867a3843db05aa1d3c5b79089308f20 100644 (file)
--- a/elf2flt.c
+++ b/elf2flt.c
@@ -257,7 +257,8 @@ output_relocs (
   asymbol **symbols,
   int number_of_symbols,
   unsigned long *n_relocs,
-  unsigned char *text, int text_len, unsigned char *data, int data_len,
+  unsigned char *text, int text_len, unsigned long text_vma,
+  unsigned char *data, int data_len, unsigned long data_vma,
   bfd *rel_bfd)
 {
   unsigned long                *flat_relocs;
@@ -335,9 +336,9 @@ dump_symbols(symbols, number_of_symbols);
         *      Only relocate things in the data sections if we are PIC/GOT.
         *      otherwise do text as well
         */
-       if (!pic_with_got && strcmp(".text", a->name) == 0)
+       if (!pic_with_got && (a->flags & SEC_CODE))
                sectionp = text;
-       else if (strcmp(".data", a->name) == 0)
+       else if (a->flags & SEC_DATA)
                sectionp = data;
        else
                continue;
@@ -972,6 +973,23 @@ static void usage(void)
 }
 
 
+/* Write NUM zeroes to STREAM.  */
+static void write_zeroes (unsigned long num, FILE *stream)
+{
+  char zeroes[1024];
+  if (num > 0) {
+    /* It'd be nice if we could just use fseek, but that doesn't seem to
+       work for stdio output files.  */
+    bzero(zeroes, 1024);
+    while (num > sizeof zeroes) {
+      fwrite(zeroes, num, 1, stream);
+      num -= sizeof zeroes;
+    }
+    if (num > 0)
+      fwrite(zeroes, num, 1, stream);
+  }
+}
+
 
 int main(int argc, char *argv[])
 {
@@ -990,14 +1008,14 @@ int main(int argc, char *argv[])
   asymbol **symbol_table;
   long number_of_symbols;
 
-  unsigned long data_len;
-  unsigned long bss_len;
-  unsigned long text_len;
+  unsigned long data_len = 0;
+  unsigned long bss_len = 0;
+  unsigned long text_len = 0;
   unsigned long reloc_len;
 
-  unsigned long data_vma;
-  unsigned long bss_vma;
-  unsigned long text_vma;
+  unsigned long data_vma = ~0;
+  unsigned long bss_vma = ~0;
+  unsigned long text_vma = ~0;
 
   void *text;
   void *data;
@@ -1108,38 +1126,62 @@ int main(int argc, char *argv[])
 
   symbol_table = get_symbols(abs_bfd, &number_of_symbols);
 
-  s = bfd_get_section_by_name (abs_bfd, ".text");
-  text_vma = s->vma;
-  text_len = s->_raw_size;
+  /* Group output sections into text, data, and bss, and calc their sizes.  */
+  for (s = abs_bfd->sections; s != NULL; s = s->next) {
+    unsigned long *vma, *len;
+
+    if (s->flags & SEC_CODE) {
+      vma = &text_vma;
+      len = &text_len;
+    } else if (s->flags & SEC_DATA) {
+      vma = &data_vma;
+      len = &data_len;
+    } else if (s->flags & SEC_ALLOC) {
+      vma = &bss_vma;
+      len = &bss_len;
+    } else
+      continue;
+
+    if (s->vma < *vma) {
+      if (*len > 0)
+       *len += s->vma - *vma;
+      else
+       *len = s->_raw_size;
+      *vma = s->vma;
+    } else if (s->vma + s->_raw_size > *vma + *len)
+      *len = s->vma + s->_raw_size - *vma;
+  }
+
+  if (text_len == 0) {
+    fprintf (stderr, "%s: no .text section", abs_file);
+    exit (2);
+  }
+
   text = malloc(text_len);
 
-  if (verbose) {
+  if (verbose)
     printf("TEXT -> vma=%x len=%x\n", text_vma, text_len);
-    printf("        lma=%x clen=%x oo=%x ap=%x fp=%x\n",
-                       s->lma, s->_cooked_size, s->output_offset,
-                       s->alignment_power, s->filepos);
-  }
 
-  if (bfd_get_section_contents(abs_bfd,
-                              s, 
-                              text,
-                              0,
-                              s->_raw_size) == false) {
-    fprintf(stderr, "read error section %s\n", s->name);
-    exit(2);
-  }
+  /* Read in all text sections.  */
+  for (s = abs_bfd->sections; s != NULL; s = s->next)
+    if (s->flags & SEC_CODE) 
+      if (bfd_get_section_contents(abs_bfd, s,
+                                  text + (s->vma - text_vma), 0,
+                                  s->_raw_size) == false)
+      {
+       fprintf(stderr, "read error section %s\n", s->name);
+       exit(2);
+      }
 
-  s = bfd_get_section_by_name (abs_bfd, ".data");
-  data_vma = s->vma;
-  data_len = s->_raw_size;
+  if (data_len == 0) {
+    fprintf (stderr, "%s: no .data section", abs_file);
+    exit (2);
+  }
   data = malloc(data_len);
 
-  if (verbose) {
-     printf("DATA -> vma=%x len=%x\n", data_vma, data_len);
-     printf("        lma=%x clen=%x oo=%x ap=%x fp=%x\n",
-                       s->lma, s->_cooked_size, s->output_offset,
-                       s->alignment_power, s->filepos);
-  }
+  if (verbose)
+    printf("DATA -> vma=%x len=%x\n", data_vma, data_len);
+
   if ((text_vma + text_len) != data_vma) {
     if ((text_vma + text_len) > data_vma) {
       printf("ERROR: text=%x overlaps data=%x ?\n", text_len, data_vma);
@@ -1151,26 +1193,22 @@ int main(int argc, char *argv[])
     text_len = data_vma - text_vma;
   }
 
-  if (bfd_get_section_contents(abs_bfd,
-                              s, 
-                              data,
-                              0,
-                              s->_raw_size) == false) {
-    fprintf(stderr, "read error section %s\n", s->name);
-    exit(2);
-  }
+  /* Read in all data sections.  */
+  for (s = abs_bfd->sections; s != NULL; s = s->next)
+    if (s->flags & SEC_DATA) 
+      if (bfd_get_section_contents(abs_bfd, s,
+                                  data + (s->vma - data_vma), 0,
+                                  s->_raw_size) == false)
+      {
+       fprintf(stderr, "read error section %s\n", s->name);
+       exit(2);
+      }
 
-  s = bfd_get_section_by_name (abs_bfd, ".bss");
-  bss_len = s->_raw_size;
-  bss_vma = s->vma;
+  /* Put common symbols in bss.  */
   bss_len += add_com_to_bss(symbol_table, number_of_symbols, bss_len);
 
-  if (verbose) {
-       printf("BSS  -> vma=%x len=%x\n", bss_vma, bss_len);
-    printf("        lma=%x clen=%x oo=%x ap=%x fp=%x\n",
-                       s->lma, s->_cooked_size, s->output_offset,
-                       s->alignment_power, s->filepos);
-  }
+  if (verbose)
+    printf("BSS  -> vma=%x len=%x\n", bss_vma, bss_len);
 
   if ((text_vma + text_len + data_len) != bss_vma) {
     if ((text_vma + text_len + data_len) > bss_vma) {
@@ -1184,8 +1222,9 @@ int main(int argc, char *argv[])
       data_len = bss_vma - data_vma;
   }
 
-  reloc = (unsigned long *) output_relocs (abs_bfd, symbol_table,
-      number_of_symbols, &reloc_len, text, text_len, data, data_len, rel_bfd);
+  reloc = (unsigned long *)
+    output_relocs(abs_bfd, symbol_table, number_of_symbols, &reloc_len,
+                 text, text_len, text_vma, data, data_len, data_vma, rel_bfd);
 
   if (reloc == NULL)
     printf("No relocations in code!\n");
@@ -1198,7 +1237,7 @@ int main(int argc, char *argv[])
   hdr.data_end    = htonl(16 * 4 + text_len + data_len);
   hdr.bss_end     = htonl(16 * 4 + text_len + data_len + bss_len);
   hdr.stack_size  = htonl(stack); /* FIXME */
-  hdr.reloc_start = htonl(16 * 4 + text_len + data_len);
+  hdr.reloc_start = htonl(16 * 4 + data_vma + data_len);
   hdr.reloc_count = htonl(reloc_len);
   hdr.flags       = htonl(0
          | (load_to_ram ? FLAT_FLAG_RAM : 0)
@@ -1254,16 +1293,25 @@ int main(int argc, char *argv[])
   if (compress == 1)
        START_COMPRESSOR;
 
+  /* Fill in any hole at the beginning of the text segment.  */
+  write_zeroes (text_vma, gf);
+
+  /* Write the text segment.  */
   fwrite(text, text_len, 1, gf);
 
   if (compress == 2)
        START_COMPRESSOR;
 
+  /* Fill in any hole at the beginning of the data segment.  */
+  write_zeroes (data_vma - (text_vma + text_len), gf);
+
+  /* Write the data segment.  */
   fwrite(data, data_len, 1, gf);
+
   if (reloc)
     fwrite(reloc, reloc_len*4, 1, gf);
+
   fclose(gf);
 
   exit(0);
 }
-