Data Structures
Here are the data structures with brief descriptions:
[detail level 12]
 C_queue
 Caco_save_T
 Caffentry_S
 Cafffile_S
 Caffheader_S
 CAPIToMPObjectStackItem
 Carg_node
 Cargentry
 Carglist
 CArray
 Cattr_entry
 CAutoCmd
 CAutoPat
 CAutoPatCmd
 Cbackpos_S
 Cbhdr
 Cblock0
 Cblock_def
 Cbt_regprog_T
 Cbuf_state
 Cbuffblock
 Cbuffheader
 CBufhlItem
 CBufhlLine
 CBufhlLineInfo
 Cbufinfo_TStructure passed around between undofile functions
 Cbufref_T
 CBufUpdateCallbacks
 Cbw_info
 CCallback
 CCallbackReader
 Ccaller_scope
 CChannel
 CChannelCallFrame
 Ccleanup_stuff
 Ccmdarg_S
 Ccmdline_info
 CCmdlineColorChunk
 Ccmdmod_T
 CcmdnameStructure for command definition
 Ccolor_name_table_T
 Ccommand_line_state
 Ccompitem_S
 Ccompl_S
 Ccondstack
 CContainerStackItemHelper structure for container_struct
 CContext
 Ccontext_sha256_T
 CconvertStruct
 Ccpp_baseclass_cache_T
 Ccscmd_T
 Ccsi
 Ccursor_entry
 Cdata_block
 Cdbg_stuff
 Cdebuggy
 Cdecomp_T
 Cdict_T
 Cdict_watcherStructure holding dictionary watcher
 CDictionary
 Cdictitem_T
 Cdictvar_SStructure representing a Dictionary
 Cdiffblock_S
 Cdiffin_T
 Cdiffio_T
 Cdiffout_T
 Cdigraph
 Cdir_stack_T
 CDirectory
 CDynamicBuffer
 Cefm_S
 CEncodedDataHelper structure for vim_to_object
 CError
 Ceslist_elem
 CexargArguments used for Ex commands
 Cexpand
 Cexpr_ast_nodeStructure representing one AST node
 CExprASTStructure representing complety AST for one expression
 CExprASTConvStackItem
 CExprASTErrorAST error definition
 Cff_search_ctx_T
 Cff_stack
 Cff_visited
 Cff_visited_list_hdr
 Cfile_buffer
 CFileDescriptorStructure used to read from/write to file
 CFileIDStruct which encapsulates inode/dev_id information
 CFileInfoStruct which encapsulates stat information
 CfilemarkStructure defining single local mark
 CFileMarksStructure that holds one file marks
 Cfline_T
 CFloatConfig
 Cfold_T
 Cfoldinfo
 Cforinfo_T
 CFrag
 Cframe_S
 Cfromto_S
 CfstStructure holding VimL function definition
 Cfunc_line
 Cfunccall_SStructure used by trans_function_name()
 Cfuncdict_T
 CGetListLineCookie
 Cgrowarray
 Chashitem_S
 Chashmap
 Chashtable_S
 Chist_entryHistory entry definition
 Chistindex
 CHistoryMergerState
 Chl_group
 CHlEntry
 Chm_llist_entryOne entry in sized linked list
 CHMLListSized linked list structure for history merger
 Cht_stack_SStructure used for explicit stack while garbage collecting hash tables
 Cinfo_pointer
 Cinsert_state
 Cinterval
 Ckey_value_pair
 Ckeyentry
 Ckmap_TStructure used for b_kmap_ga.ga_data
 Clangmap_entry_T
 Clangp_S
 CLastSetStores an identifier of a script or channel that last set an option
 CLexExprTokenLexer token
 Clibuv_process
 Climitscore_T
 Clineoff_T
 CLineState
 Clist_stack_SStructure used for explicit stack while garbage collecting lists
 Clistitem_S
 CListReaderStateStructure defining state for read_from_list()
 CListSortItemStructure representing one list item, used for sort array
 Clistvar_S
 Clistwatch_S
 Cllpos_TSame as lpos_T, but with additional field len
 Cloop
 Cloop_cookie
 Clpos_T
 CLuaError
 CLuaTablePropsDetermine, which keys lua table contains
 Clval_S
 Cmap_arguments
 Cmapblock
 Cmatch_T
 Cmatchinf_S
 Cmatchitem
 CmemfileA memory file
 Cmemline
 Cmenutrans_T
 Cmessage
 Cmf_blocknr_trans_item
 Cmf_hashitem
 Cmf_hashtab
 Cml_chunksize
 Cmparm_T
 CMPConvStackValStructure representing current VimL to messagepack conversion state
 CMPToAPIObjectStackItem
 Cmsg_histMessage history for :messages
 Cmsgchunk_S
 Cmsglist
 CMsgpackRpcRequestHandler
 Cmultiqueue
 Cmultiqueue_item
 Cname_list
 Cnfa_list_T
 Cnfa_pim_S
 Cnfa_regprog_T
 Cnfa_state
 Cnfa_thread_T
 Cnormal_state
 Cnvim_stats_s
 Cobject
 CObjPopStackItemHelper structure for nlua_pop_Object
 Coparg_S
 Coption_table_T
 CParserHighlightChunk
 CParserInputReaderStructure defining input reader
 CParserLineOne parsed line
 CParserPositionParser position in the input
 CParserStateStructure defining parser state
 CParserStateItemParser state item
 Cpartial_S
 Cpat_T
 Cpointer_block
 Cpointer_entry
 Cpos_save_T
 Cpos_T
 Cposmatch
 CPossiblyFreedShadaEntryShadaEntry structure that knows whether it should be freed
 CPreviewLines
 Cprocess
 Cprt_dsc_comment_S
 Cprt_dsc_line_S
 Cprt_mediasize_S
 Cprt_pos_T
 Cprt_ps_charset_S
 Cprt_ps_encoding_S
 Cprt_ps_font_S
 Cprt_ps_mbfont_S
 Cprt_ps_resource_S
 Cprt_resfile_buffer_S
 Cprt_settings_T
 Cprt_text_attr_T
 CPtrlist
 Cpty_process
 Cpumitem_TUsed for popup menu items
 Cqf_info_S
 Cqf_list_S
 Cqffields_T
 Cqfline_S
 Cqfstate_T
 Crbuffer
 CRect
 Creg_extmatch
 Cregbehind_S
 Cregengine
 Cregexec_T
 Cregion
 Cregitem_S
 Cregmatch_T
 Cregmmatch_T
 Cregprog
 Cregsave_T
 Cregstar_S
 Cregsub_T
 Cregsubmatch_T
 Cregsubs_T
 CRequestEvent
 CRpcState
 Cs_bdiffparam
 Cs_chanode
 Cs_chastore
 Cs_diffdata
 Cs_mmbuffer
 Cs_mmfile
 Cs_xdalgoenv
 Cs_xdchange
 Cs_xdemitcb
 Cs_xdemitconf
 Cs_xdfenv
 Cs_xdfile
 Cs_xdlclass
 Cs_xdlclassifier
 Cs_xdpsplit
 Cs_xmparam
 Cs_xpparam
 Cs_xrecord
 Csalitem_S
 Csave_redo_T
 Csave_se_T
 Csblock_S
 CScreenGrid
 Cscriptitem_S
 Cscriptvar_T
 CScrollbackLine
 Csd_read_defStructure containing necessary pointers for reading ShaDa files
 Csd_write_defStructure containing necessary pointers for writing ShaDa files
 CSearchedFile
 Csftword_T
 CShadaEntryStructure defining a single ShaDa file entry
 Csign
 Csignal_watcher
 Csigngroup_S
 Csignlist
 Cslang_S
 Csn_prl_S
 Csocket_watcher
 Csoffset
 Csorti_TStruct to store info to be sorted
 Csortinfo_TStruct storing information about current sort
 Csource_cookie
 Csp_syn
 CspatStructure containing last search pattern and its attributes
 Cspellinfo_S
 Cspelload_S
 Cspelltab_T
 Csplit_measurement
 Csplit_score
 Cstate_item
 CstaticList10_T
 CStderrState
 CStdioPair
 Cstl_hlrec
 CStlClickDefinitionStatus line click definition
 CStlClickRecordUsed for tabline clicks
 Cstream
 CString
 CStringShift
 Csubcommand
 Csubflags_TFlags kept between calls to :substitute
 CSubReplacementStringPrevious :substitute replacement string definition
 CSubResult
 Csuggest_T
 Csuginfo_S
 Csyl_item_S
 Csyn_cluster_S
 Csyn_opt_arg_T
 Csyn_pattern
 Csyn_state
 Csyn_time_T
 Csynblock_T
 Ctabpage_S
 Ctag_pointers
 Ctaggy
 Ctagname_T
 Ctasave_T
 Cterm_input
 Cterminal
 Cterminal_state
 CTerminalOptions
 Ctime_entry_T
 Ctime_watcher
 Ctimer_T
 CTryState
 Ctrystate_S
 CTUIData
 CTVPopStackItemHelper structure for nlua_pop_typval
 Ctypebuf_T
 Ctypval_TStructure that holds an internal variable value
 Cu_entry
 Cu_header
 Cucell
 Cucmd
 CufuncStructure to hold info for a user function
 Cugrid
 Cui_bridge_data
 Cui_t
 CUIData
 Cuv_pipe_s
 CValuesStackItemHelper structure for values struct
 Cvim_exception
 Cvim_state
 Cvimconv_TStructure used for string conversions
 CVimMenu
 Cvimoption
 CVirtTextChunk
 Cvisualinfo_T
 Cw_line
 Cwbuffer
 Cwcmd_T
 Cwindow_S
 Cwininfo_S
 Cwinopt_T
 Cwordcount_S
 Cwordnode_S
 CWRequest
 CWriteMergerState
 Cxdlgroup
 CxfilemarkStructure defining extended mark (mark with file name attached)
 CyankregDefinition of one register