60 lines
1.8 KiB
C
60 lines
1.8 KiB
C
#ifndef EINA_MMAP_H_
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#define EINA_MMAP_H_
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/**
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* @addtogroup Eina_Mmap_Group Mmap Group
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*
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* @brief These functions provide helpers for safe mmap handling
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*
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* @{
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*
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* @since 1.1.0
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*/
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/**
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* @brief Enable or disable safe mmaped IO handling
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*
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* @param enabled The enabled state (to enable, pass EINA_TRUE)
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*
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* This enables (if possible on your platform) a signal handler for
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* SIGBUS, that replaces the "bad page" with a pzge of 0's (from /dev/zero)
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* if a SIGBUS occurs. This allows for safe mmap() of files that may truncate
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* or from files on devices with IO errors. Normally these cases will result
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* in a SIGBUS being delivered (and termination of yyour process), but
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* when "mmap safety" is enabled, this will not occur. Instead a page of
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* bytes of the value 0 will replace the "bad page", allowing the process
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* to continue and allow its own parsing error detection to safely abort
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* the operation without the process falling apart.
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*
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* If you disable mmap safety, the SIGBUS handler will be restored to its
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* default handler. Note that eina_file_map_all() and eina_file_map_new()
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* will automatically enable mmap safety as they provide an mmaped file IO
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* layer, and rely on mmap to not fail for any part of the file.
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*
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* If you set up your own SIGBUS handler, then this will effectively disable
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* the safe mmap handling and make you liable to crashes on IO to or from
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* such "damaged files" that would take down your process.
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*
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* @since 1.1.0
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*/
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EAPI Eina_Bool
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eina_mmap_safety_enabled_set(Eina_Bool enabled);
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/**
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* @brief Get the enabled state of mmap safety.
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*
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* @return The safety state (EINA_TRUE if enabled)
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*
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* This returns the mmap safety state set by eina_mmap_safety_enabled_set().
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* See eina_mmap_safety_enabled_set() for more information.
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*
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* @since 1.1.0
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*/
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EAPI Eina_Bool
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eina_mmap_safety_enabled_get(void);
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/**
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* @}
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*/
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#endif
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