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Enforce power-of-two for history setting in CMakeLists (#271)
* STREAM_HISTORY option requires power-of-two value Signed-off-by: gavanderhoorn <g.a.vanderhoorn@tudelft.nl> * Also mention power-of-two requirement in readme Signed-off-by: gavanderhoorn <g.a.vanderhoorn@tudelft.nl> * cmake: enforce power-of-two for history setting Signed-off-by: gavanderhoorn <g.a.vanderhoorn@tudelft.nl> Signed-off-by: gavanderhoorn <g.a.vanderhoorn@tudelft.nl>
1 parent a2a7484 commit fb2dca6

2 files changed

Lines changed: 34 additions & 7 deletions

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‎README.md‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -51,9 +51,9 @@ All the configurable parameters are:
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| RMW_UXRCE_ENTITY_CREATION_TIMEOUT | This value sets the maximum time to wait for an XRCE entity creation </br> in milliseconds. If set to 0 best effort is used. | 1000 |
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| RMW_UXRCE_ENTITY_DESTROY_TIMEOUT | This value sets the maximum time to wait for an XRCE entity destroy </br> in milliseconds. If set to 0 best effort is used. | 1000 |
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| RMW_UXRCE_PUBLISH_RELIABLE_TIMEOUT | This value sets the default time to wait for a publication in a </br> reliable mode in milliseconds. | 1000 |
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| RMW_UXRCE_STREAM_HISTORY | This value sets the number of MTUs to buffer, both input and output. | 4 |
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| RMW_UXRCE_STREAM_HISTORY_INPUT | This value sets the number of MTUs to input buffer. </br> It will be ignored if RMW_UXRCE_STREAM_HISTORY_OUTPUT is blank. | - |
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| RMW_UXRCE_STREAM_HISTORY_OUTPUT | This value sets the number of MTUs to output buffer. </br> It will be ignored if RMW_UXRCE_STREAM_HISTORY_INPUT is blank. | - |
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| RMW_UXRCE_STREAM_HISTORY | This value sets the number of MTUs to buffer, both input and output. Must be a power-of-two. | 4 |
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| RMW_UXRCE_STREAM_HISTORY_INPUT | This value sets the number of MTUs to input buffer. </br> It will be ignored if RMW_UXRCE_STREAM_HISTORY_OUTPUT is blank. If set, must be a power-of-two. | - |
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| RMW_UXRCE_STREAM_HISTORY_OUTPUT | This value sets the number of MTUs to output buffer. </br> It will be ignored if RMW_UXRCE_STREAM_HISTORY_INPUT is blank. If set, must be a power-of-two. | - |
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| RMW_UXRCE_GRAPH | Allows to perform graph-related operations to the user | OFF |
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| RMW_UXRCE_ALLOW_DYNAMIC_ALLOCATIONS | Enables increasing static pools with dynamic allocation when needed. | OFF |
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‎rmw_microxrcedds_c/CMakeLists.txt‎

Lines changed: 31 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -84,17 +84,44 @@ if(RMW_UXRCE_ENTITY_DESTROY_TIMEOUT STREQUAL "")
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set(RMW_UXRCE_ENTITY_DESTROY_TIMEOUT ${RMW_UXRCE_ENTITY_CREATION_DESTROY_TIMEOUT})
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endif()
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set(RMW_UXRCE_STREAM_HISTORY "4" CACHE STRING "This value sets the number of MTUs to buffer, both input and output.")
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set(RMW_UXRCE_STREAM_HISTORY "4" CACHE STRING
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"This value sets the number of MTUs to buffer, both input and output. Must be a power of two.")
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set(RMW_UXRCE_STREAM_HISTORY_INPUT "" CACHE STRING
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"This value sets the number of MTUs to input buffer. It will be ignored if RMW_UXRCE_STREAM_HISTORY_OUTPUT is blank.")
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"This value sets the number of MTUs to input buffer. It will be ignored if RMW_UXRCE_STREAM_HISTORY_OUTPUT is blank. \
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If set, must be a power of two.")
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set(RMW_UXRCE_STREAM_HISTORY_OUTPUT "" CACHE STRING
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"This value sets the number of MTUs to output buffer. It will be ignored if RMW_UXRCE_STREAM_HISTORY_INPUT is blank.")
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"This value sets the number of MTUs to output buffer. It will be ignored if RMW_UXRCE_STREAM_HISTORY_INPUT is blank. \
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If set, must be a power of two.")
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if(RMW_UXRCE_STREAM_HISTORY_INPUT STREQUAL "" OR RMW_UXRCE_STREAM_HISTORY_OUTPUT STREQUAL "")
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unset(RMW_UXRCE_STREAM_HISTORY_INPUT)
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unset(RMW_UXRCE_STREAM_HISTORY_OUTPUT)
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# check power-of-two requirement
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# from: http://graphics.stanford.edu/~seander/bithacks.html#DetermineIfPowerOf2
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math(EXPR __RMW_UXRCE_STREAM_HISTORY_CHECK "${RMW_UXRCE_STREAM_HISTORY} & (${RMW_UXRCE_STREAM_HISTORY} - 1)")
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if(${__RMW_UXRCE_STREAM_HISTORY_CHECK} GREATER 0)
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message(FATAL_ERROR "STREAM_HISTORY must be a power-of-two (not: ${RMW_UXRCE_STREAM_HISTORY})")
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endif()
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unset(__RMW_UXRCE_STREAM_HISTORY_CHECK)
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else()
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unset(RMW_UXRCE_STREAM_HISTORY)
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# check power-of-two requirement
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# from: http://graphics.stanford.edu/~seander/bithacks.html#DetermineIfPowerOf2
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math(EXPR __RMW_UXRCE_STREAM_HISTORY_INPUT_CHECK "${RMW_UXRCE_STREAM_HISTORY_INPUT} & (${RMW_UXRCE_STREAM_HISTORY_INPUT} - 1)")
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math(EXPR __RMW_UXRCE_STREAM_HISTORY_OUTPUT_CHECK "${RMW_UXRCE_STREAM_HISTORY_OUTPUT} & (${RMW_UXRCE_STREAM_HISTORY_OUTPUT} - 1)")
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if(${__RMW_UXRCE_STREAM_HISTORY_INPUT_CHECK} GREATER 0)
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message(FATAL_ERROR "STREAM_HISTORY_INPUT must be a power-of-two (not: ${RMW_UXRCE_STREAM_HISTORY_INPUT})")
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endif()
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if(${__RMW_UXRCE_STREAM_HISTORY_OUTPUT_CHECK} GREATER 0)
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message(FATAL_ERROR "STREAM_HISTORY_OUTPUT must be a power-of-two (not: ${RMW_UXRCE_STREAM_HISTORY_OUTPUT})")
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endif()
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unset(__RMW_UXRCE_STREAM_HISTORY_INPUT_CHECK)
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unset(__RMW_UXRCE_STREAM_HISTORY_OUTPUT_CHECK)
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endif()
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# Transport handle define macros.
@@ -402,4 +429,4 @@ if(BUILD_DOCUMENTATION)
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install(DIRECTORY ${PROJECT_BINARY_DIR}/doc/api_reference
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DESTINATION ${DOC_INSTALL_DIR}
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COMPONENT documentation)
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endif()
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endif()

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