IPC: Difference between revisions
What a mess. Let's try to clean it up a bit. |
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| type | | Translation type | ||
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The type of parameter is described by the bits 1-3 in the translation descriptor. Parameter types accepted for sending by the kernel are: 0, 1, 2, 5, 6, 7. | The type of parameter is described by the bits 1-3 in the translation descriptor. Parameter types accepted for sending by the kernel are: 0, 1, 2, 5, 6, 7. | ||
For replies, only 0, 1, 5, 6, 7 are allowed. In other words any type 2 fields must be zeroed before calling svcReplyAndReceive on the server-side. For replies, type 0, 1, and 2 are ignored. Types 5, 6, and 7 do something with the mem pointer upon reply. The type 0 descriptor can be used to ignore parameters. The number of parameters covered by a type-0 descriptor is (desc >> 26) + 1. | |||
== Handle Translation == | |||
Translation type 0 is used to send handles across processes. The corresponding translation descriptor has the following structure: | |||
{| class="wikitable" border="1" | {| class="wikitable" border="1" | ||
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|} | |} | ||
Usage examples: | |||
{| class="wikitable" border="1" | {| class="wikitable" border="1" | ||
|- | |- | ||
! scope="col" width="300" | Usual form | ! scope="col" width="300" | Usual form | ||
! Description | ! Description | ||
|- | |- | ||
| 0x00000000 <nowiki>|</nowiki> ((num_handles-1)<<26) | | 0x00000000 <nowiki>|</nowiki> ((num_handles-1)<<26) | ||
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| Copies the given KHandles to the receiving process, i.e. creating new handles in the target process while keeping around the ones of the source process. When a handle value is 0x0, value 0x0 is written to the destination cmdbuf without doing any actual handle-transfer. | | Copies the given KHandles to the receiving process, i.e. creating new handles in the target process while keeping around the ones of the source process. When a handle value is 0x0, value 0x0 is written to the destination cmdbuf without doing any actual handle-transfer. | ||
|- | |- | ||
| 0x00000010 <nowiki>|</nowiki> ((num_handles-1)<<26) | | 0x00000010 <nowiki>|</nowiki> ((num_handles-1)<<26) | ||
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| Moves the given KHandles to the receiving process, i.e. creating new handles in the target process and closing the ones of the source process. When a handle value is 0x0, value 0x0 is written to the destination cmdbuf without doing any actual handle-transfer. | | Moves the given KHandles to the receiving process, i.e. creating new handles in the target process and closing the ones of the source process. When a handle value is 0x0, value 0x0 is written to the destination cmdbuf without doing any actual handle-transfer. | ||
|- | |- | ||
| 0x00000020 | | 0x00000020 | ||
<placeholder> | <placeholder> | ||
| Let kernel set value to calling process ProcessID. | | Let kernel set value to calling process ProcessID. | ||
|} | |||
== Usage Examples for other Translation Types == | |||
{| class="wikitable" border="1" | |||
|- | |||
! Type | |||
! scope="col" width="300" | Usual form | |||
! Description | |||
|- | |- | ||
| 1 | | 1 | ||