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Revision 64 - (hide annotations)
Fri Dec 15 00:21:51 2000 UTC (23 years, 10 months ago) by frodo
File size: 1857 byte(s)
(Frodo) Massive update: theoretically, all return codes are now checked.
        Untested - may have many typos.

1 frodo 64 Major parsing routines are built according to this template:
2    
3     int psiconv_parse_TYPE (const psiconv_buffer buf, int lev,
4     psiconv_u32 off, int *length,
5     psiconv_TYPE *result)
6     {
7     int res = 0;
8     int len = 0;
9     int leng;
10    
11     psiconv_progress(lev+1,off,"Going to parse TYPE");
12     if (!(*result = malloc(sizeof(**result))))
13     goto ERROR1;
14    
15     /* Example of calling some other parse function */
16     if ((res = psiconv_parse_TYPE2(buf,lev+2,off+len,&leng,
17     &(*result)->FIELD2)))
18     goto ERROR2;
19     psiconv_debug(lev+2,off+len,"Some helpful message");
20     len += leng;
21    
22     /* Example of reading some bytes directly */
23     (*result)->FIELD1 = psiconv_read_u8(buf,lev+2,off+len,&res);
24     if (!res)
25     goto ERROR3;
26     psiconv_debug(lev+2,off+len,"Some helpful message");
27     len ++;
28    
29     psiconv_debug(lev+2,off+len,"Some helpful message");
30     if (length)
31     *length = len;
32     psiconv_progress(lev+1,off+len-1,"End of TYPE (total length: %08x)",
33     len);
34     return 0;
35    
36     ERROR3:
37     free ((*result)->FIELD2)
38     ERROR2:
39     free (*result);
40     ERROR1:
41     psiconv_warn(lev+1,off,"Reading of TYPE failed");
42     if (length)
43     *length = 0;
44     if (!res)
45     return -PSICONV_E_NOMEM;
46     else
47     return res;
48     }
49    
50     If something unexpected happens half-way, but you can recover from it
51     (for example, an unexpected value in some well-defined field), call
52     psiconv_warn, but do not return with an error. The rule is that if
53     the result code of a procedure is not 0, you may assume that things
54     are hopeless, that nothing was allocated, and that every field contains
55     nonsense.

frodo@frodo.looijaard.name
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