author | andrew.jordan <> |
Thu, 29 Jul 2010 11:34:55 +0100 | |
branch | GCC_SURGE |
changeset 90 | 73ba398cc7f4 |
parent 1 | 2fb8b9db1c86 |
permissions | -rw-r--r-- |
1
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Initial QEMU (symbian-qemu-0.9.1-12) import
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1 |
/*=== |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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2 |
cexcept.h 2.0.1 (2008-Jul-19-Sat) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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3 |
http://www.nicemice.net/cexcept/ |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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4 |
Adam M. Costello |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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5 |
http://www.nicemice.net/amc/ |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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6 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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7 |
An interface for exception-handling in ANSI C (C89 and subsequent ISO |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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8 |
standards), developed jointly with Cosmin Truta. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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9 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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10 |
Copyright (c) 2000-2008 Adam M. Costello and Cosmin Truta. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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11 |
This software may be modified only if its author and version |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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12 |
information is updated accurately, and may be redistributed |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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13 |
only if accompanied by this unaltered notice. Subject to those |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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14 |
restrictions, permission is granted to anyone to do anything |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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15 |
with this software. The copyright holders make no guarantees |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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16 |
regarding this software, and are not responsible for any damage |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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17 |
resulting from its use. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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18 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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19 |
The cexcept interface is not compatible with and cannot interact |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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20 |
with system exceptions (like division by zero or memory segmentation |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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21 |
violation), compiler-generated exceptions (like C++ exceptions), or |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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other exception-handling interfaces. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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23 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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24 |
When using this interface across multiple .c files, do not include |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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25 |
this header file directly. Instead, create a wrapper header file that |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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includes this header file and then invokes the define_exception_type |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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macro (see below). The .c files should then include that header file. |
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28 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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The interface consists of one type, one well-known name, and six macros. |
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30 |
|
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31 |
|
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define_exception_type(type_name); |
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33 |
|
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This macro is used like an external declaration. It specifies |
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the type of object that gets copied from the exception thrower to |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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36 |
the exception catcher. The type_name can be any type that can be |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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assigned to, that is, a non-constant arithmetic type, struct, union, |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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or pointer. Examples: |
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39 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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define_exception_type(int); |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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41 |
|
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enum exception { out_of_memory, bad_arguments, disk_full }; |
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define_exception_type(enum exception); |
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44 |
|
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struct exception { int code; const char *msg; }; |
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define_exception_type(struct exception); |
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47 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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48 |
Because throwing an exception causes the object to be copied (not |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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49 |
just once, but twice), programmers may wish to consider size when |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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50 |
choosing the exception type. |
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51 |
|
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52 |
|
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struct exception_context; |
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54 |
|
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55 |
This type may be used after the define_exception_type() macro has |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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56 |
been invoked. A struct exception_context must be known to both |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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57 |
the thrower and the catcher. It is expected that there be one |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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58 |
context for each thread that uses exceptions. It would certainly |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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59 |
be dangerous for multiple threads to access the same context. |
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60 |
One thread can use multiple contexts, but that is likely to be |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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61 |
confusing and not typically useful. The application can allocate |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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62 |
this structure in any way it pleases--automatic, static, or dynamic. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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63 |
The application programmer should pretend not to know the structure |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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64 |
members, which are subject to change. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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65 |
|
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66 |
|
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67 |
struct exception_context *the_exception_context; |
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68 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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69 |
The Try/Catch and Throw statements (described below) implicitly |
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70 |
refer to a context, using the name the_exception_context. It is |
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71 |
the application's responsibility to make sure that this name yields |
2fb8b9db1c86
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72 |
the address of a mutable (non-constant) struct exception_context |
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wherever those statements are used. Subject to that constraint, the |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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74 |
application may declare a variable of this name anywhere it likes |
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75 |
(inside a function, in a parameter list, or externally), and may |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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76 |
use whatever storage class specifiers (static, extern, etc) or type |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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77 |
qualifiers (const, volatile, etc) it likes. Examples: |
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78 |
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79 |
static struct exception_context |
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80 |
* const the_exception_context = &foo; |
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81 |
|
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82 |
{ struct exception_context *the_exception_context = bar; ... } |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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83 |
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84 |
int blah(struct exception_context *the_exception_context, ...); |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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85 |
|
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86 |
extern struct exception_context the_exception_context[1]; |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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87 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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88 |
The last example illustrates a trick that avoids creating a pointer |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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object separate from the structure object. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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90 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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91 |
The name could even be a macro, for example: |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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92 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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93 |
struct exception_context ec_array[numthreads]; |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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94 |
#define the_exception_context (ec_array + thread_id) |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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95 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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96 |
Be aware that the_exception_context is used several times by the |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
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97 |
Try/Catch/Throw macros, so it shouldn't be expensive or have side |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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98 |
effects. The expansion must be a drop-in replacement for an |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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99 |
identifier, so it's safest to put parentheses around it. |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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100 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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101 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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102 |
void init_exception_context(struct exception_context *ec); |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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103 |
|
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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104 |
For context structures allocated statically (by an external |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
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105 |
definition or using the "static" keyword), the implicit |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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106 |
initialization to all zeros is sufficient, but contexts allocated |
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Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
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107 |
by other means must be initialized using this macro before they |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
108 |
are used by a Try/Catch statement. It does no harm to initialize |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
109 |
a context more than once (by using this macro on a statically |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
110 |
allocated context, or using this macro twice on the same context), |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
111 |
but a context must not be re-initialized after it has been used by a |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
112 |
Try/Catch statement. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
113 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
114 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
115 |
Try statement |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
116 |
Catch (expression) statement |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
117 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
118 |
The Try/Catch/Throw macros are capitalized in order to avoid |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
119 |
confusion with the C++ keywords, which have subtly different |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
120 |
semantics. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
121 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
122 |
A Try/Catch statement has a syntax similar to an if/else statement, |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
123 |
except that the parenthesized expression goes after the second |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
124 |
keyword rather than the first. As with if/else, there are two |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
125 |
clauses, each of which may be a simple statement ending with a |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
126 |
semicolon or a brace-enclosed compound statement. But whereas |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
127 |
the else clause is optional, the Catch clause is required. The |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
128 |
expression must be a modifiable lvalue (something capable of being |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
129 |
assigned to) of the same type (disregarding type qualifiers) that |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
130 |
was passed to define_exception_type(). |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
131 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
132 |
If a Throw that uses the same exception context as the Try/Catch is |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
133 |
executed within the Try clause (typically within a function called |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
134 |
by the Try clause), and the exception is not caught by a nested |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
135 |
Try/Catch statement, then a copy of the exception will be assigned |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
136 |
to the expression, and control will jump to the Catch clause. If no |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
137 |
such Throw is executed, then the assignment is not performed, and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
138 |
the Catch clause is not executed. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
139 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
140 |
The expression is not evaluated unless and until the exception is |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
141 |
caught, which is significant if it has side effects, for example: |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
142 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
143 |
Try foo(); |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
144 |
Catch (p[++i].e) { ... } |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
145 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
146 |
IMPORTANT: Jumping into or out of a Try clause (for example via |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
147 |
return, break, continue, goto, longjmp) is forbidden--the compiler |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
148 |
will not complain, but bad things will happen at run-time. Jumping |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
149 |
into or out of a Catch clause is okay, and so is jumping around |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
150 |
inside a Try clause. In many cases where one is tempted to return |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
151 |
from a Try clause, it will suffice to use Throw, and then return |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
152 |
from the Catch clause. Another option is to set a flag variable and |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
153 |
use goto to jump to the end of the Try clause, then check the flag |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
154 |
after the Try/Catch statement. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
155 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
156 |
IMPORTANT: The values of any non-volatile automatic variables |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
157 |
changed within the Try clause are undefined after an exception is |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
158 |
caught. Therefore, variables modified inside the Try block whose |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
159 |
values are needed later outside the Try block must either use static |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
160 |
storage or be declared with the "volatile" type qualifier. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
161 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
162 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
163 |
Throw expression; |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
164 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
165 |
A Throw statement is very much like a return statement, except that |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
166 |
the expression is required. Whereas return jumps back to the place |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
167 |
where the current function was called, Throw jumps back to the Catch |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
168 |
clause of the innermost enclosing Try clause. The expression must |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
169 |
be compatible with the type passed to define_exception_type(). The |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
170 |
exception must be caught, otherwise the program may crash. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
171 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
172 |
Slight limitation: If the expression is a comma-expression, it must |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
173 |
be enclosed in parentheses. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
174 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
175 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
176 |
Try statement |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
177 |
Catch_anonymous statement |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
178 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
179 |
When the value of the exception is not needed, a Try/Catch statement |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
180 |
can use Catch_anonymous instead of Catch (expression). |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
181 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
182 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
183 |
Everything below this point is for the benefit of the compiler. The |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
184 |
application programmer should pretend not to know any of it, because it |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
185 |
is subject to change. |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
186 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
187 |
===*/ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
188 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
189 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
190 |
#ifndef CEXCEPT_H |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
191 |
#define CEXCEPT_H |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
192 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
193 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
194 |
#include <setjmp.h> |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
195 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
196 |
#define define_exception_type(etype) \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
197 |
struct exception_context { \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
198 |
jmp_buf *penv; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
199 |
int caught; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
200 |
volatile struct { etype etmp; } v; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
201 |
} |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
202 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
203 |
/* etmp must be volatile because the application might use automatic */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
204 |
/* storage for the_exception_context, and etmp is modified between */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
205 |
/* the calls to setjmp() and longjmp(). A wrapper struct is used to */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
206 |
/* avoid warnings about a duplicate volatile qualifier in case etype */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
207 |
/* already includes it. */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
208 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
209 |
#define init_exception_context(ec) ((void)((ec)->penv = 0)) |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
210 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
211 |
#define Try \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
212 |
{ \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
213 |
jmp_buf *exception__prev, exception__env; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
214 |
exception__prev = the_exception_context->penv; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
215 |
the_exception_context->penv = &exception__env; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
216 |
if (setjmp(exception__env) == 0) { \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
217 |
do |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
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parents:
diff
changeset
|
218 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
219 |
#define exception__catch(action) \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
220 |
while (the_exception_context->caught = 0, \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
221 |
the_exception_context->caught); \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
222 |
} \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
223 |
else { \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
224 |
the_exception_context->caught = 1; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
225 |
} \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
226 |
the_exception_context->penv = exception__prev; \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
227 |
} \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
228 |
if (!the_exception_context->caught || action) { } \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
229 |
else |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
230 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
231 |
#define Catch(e) exception__catch(((e) = the_exception_context->v.etmp, 0)) |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
232 |
#define Catch_anonymous exception__catch(0) |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
233 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
234 |
/* Try ends with do, and Catch begins with while(0) and ends with */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
235 |
/* else, to ensure that Try/Catch syntax is similar to if/else */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
236 |
/* syntax. */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
237 |
/* */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
238 |
/* The 0 in while(0) is expressed as x=0,x in order to appease */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
239 |
/* compilers that warn about constant expressions inside while(). */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
240 |
/* Most compilers should still recognize that the condition is always */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
241 |
/* false and avoid generating code for it. */ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
242 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
243 |
#define Throw \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
244 |
for (;; longjmp(*the_exception_context->penv, 1)) \ |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
245 |
the_exception_context->v.etmp = |
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
246 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
247 |
|
2fb8b9db1c86
Initial QEMU (symbian-qemu-0.9.1-12) import
martin.trojer@nokia.com
parents:
diff
changeset
|
248 |
#endif /* CEXCEPT_H */ |