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      1 /* Add signed little endian base 128 integer to a section.
      2    Copyright (C) 2002, 2005 Red Hat, Inc.
      3    This file is part of elfutils.
      4    Written by Ulrich Drepper <drepper (at) redhat.com>, 2002.
      5 
      6    This file is free software; you can redistribute it and/or modify
      7    it under the terms of either
      8 
      9      * the GNU Lesser General Public License as published by the Free
     10        Software Foundation; either version 3 of the License, or (at
     11        your option) any later version
     12 
     13    or
     14 
     15      * the GNU General Public License as published by the Free
     16        Software Foundation; either version 2 of the License, or (at
     17        your option) any later version
     18 
     19    or both in parallel, as here.
     20 
     21    elfutils is distributed in the hope that it will be useful, but
     22    WITHOUT ANY WARRANTY; without even the implied warranty of
     23    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     24    General Public License for more details.
     25 
     26    You should have received copies of the GNU General Public License and
     27    the GNU Lesser General Public License along with this program.  If
     28    not, see <http://www.gnu.org/licenses/>.  */
     29 
     30 #ifdef HAVE_CONFIG_H
     31 # include <config.h>
     32 #endif
     33 
     34 #include <inttypes.h>
     35 #include <string.h>
     36 
     37 #include <libasmP.h>
     38 
     39 
     40 int
     41 asm_addsleb128 (AsmScn_t *asmscn, int32_t num)
     42 {
     43   if (asmscn == NULL)
     44     return -1;
     45 
     46   if (asmscn->type == SHT_NOBITS && unlikely (num != 0))
     47     {
     48       __libasm_seterrno (ASM_E_TYPE);
     49       return -1;
     50     }
     51 
     52   if (unlikely (asmscn->ctx->textp))
     53     fprintf (asmscn->ctx->out.file, "\t.sleb128\t%" PRId32 "\n", num);
     54   else
     55     {
     56       char tmpbuf[(sizeof (num) * 8 + 6) / 7];
     57       char *dest = tmpbuf;
     58       uint32_t byte;
     59       int32_t endval = num >> 31;
     60 
     61       if (num == 0)
     62 	byte = 0;
     63       else
     64 	while (1)
     65 	  {
     66 	    byte = num & 0x7f;
     67 
     68 	    num >>= 7;
     69 	    if (num == endval)
     70 	      /* This is the last byte.  */
     71 	      break;
     72 
     73 	    *dest++ = byte | 0x80;
     74 	  }
     75 
     76       *dest++ = byte;
     77 
     78       /* Number of bytes produced.  */
     79       size_t nbytes = dest - tmpbuf;
     80 
     81       /* Make sure we have enough room.  */
     82       if (__libasm_ensure_section_space (asmscn, nbytes) != 0)
     83 	return -1;
     84 
     85       /* Copy the bytes.  */
     86       if (likely (asmscn->type != SHT_NOBITS))
     87 	memcpy (&asmscn->content->data[asmscn->content->len], tmpbuf, nbytes);
     88 
     89       /* Adjust the pointer in the data buffer.  */
     90       asmscn->content->len += nbytes;
     91 
     92       /* Increment the offset in the (sub)section.  */
     93       asmscn->offset += nbytes;
     94     }
     95 
     96   return 0;
     97 }
     98