/* $Id: VBoxAutostartCfg.cpp 63289 2016-08-10 15:24:06Z vboxsync $ */ /** @file * VBoxAutostart - VirtualBox Autostart service, configuration parser. */ /* * Copyright (C) 2012-2016 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #include #include #include #include #include #include #include "VBoxAutostart.h" /********************************************************************************************************************************* * Constants And Macros, Structures and Typedefs * *********************************************************************************************************************************/ /** * Token type. */ typedef enum CFGTOKENTYPE { /** Invalid token type. */ CFGTOKENTYPE_INVALID = 0, /** Identifier. */ CFGTOKENTYPE_ID, /** Comma. */ CFGTOKENTYPE_COMMA, /** Equal sign. */ CFGTOKENTYPE_EQUAL, /** Open curly brackets. */ CFGTOKENTYPE_CURLY_OPEN, /** Closing curly brackets. */ CFGTOKENTYPE_CURLY_CLOSING, /** End of file. */ CFGTOKENTYPE_EOF, /** 32bit hack. */ CFGTOKENTYPE_32BIT_HACK = 0x7fffffff } CFGTOKENTYPE; /** Pointer to a token type. */ typedef CFGTOKENTYPE *PCFGTOKENTYPE; /** Pointer to a const token type. */ typedef const CFGTOKENTYPE *PCCFGTOKENTYPE; /** * A token. */ typedef struct CFGTOKEN { /** Type of the token. */ CFGTOKENTYPE enmType; /** Line number of the token. */ unsigned iLine; /** Starting character of the token in the stream. */ size_t cchStart; /** Type dependen token data. */ union { /** Data for the ID type. */ struct { /** Size of the id in characters, excluding the \0 terminator. */ size_t cchToken; /** Token data, variable size (given by cchToken member). */ char achToken[1]; } Id; } u; } CFGTOKEN; /** Pointer to a token. */ typedef CFGTOKEN *PCFGTOKEN; /** Pointer to a const token. */ typedef const CFGTOKEN *PCCFGTOKEN; /** * Tokenizer instance data for the config data. */ typedef struct CFGTOKENIZER { /** Config file handle. */ PRTSTREAM hStrmConfig; /** String buffer for the current line we are operating in. */ char *pszLine; /** Size of the string buffer. */ size_t cbLine; /** Current position in the line. */ char *pszLineCurr; /** Current line in the config file. */ unsigned iLine; /** Current character of the line. */ size_t cchCurr; /** Flag whether the end of the config stream is reached. */ bool fEof; /** Pointer to the next token in the stream (used to peek). */ PCFGTOKEN pTokenNext; } CFGTOKENIZER, *PCFGTOKENIZER; /********************************************************************************************************************************* * Internal Functions * *********************************************************************************************************************************/ /** * Free a config token. * * @returns nothing. * @param pCfgTokenizer The config tokenizer. * @param pToken The token to free. */ static void autostartConfigTokenFree(PCFGTOKENIZER pCfgTokenizer, PCFGTOKEN pToken) { NOREF(pCfgTokenizer); RTMemFree(pToken); } /** * Reads the next line from the config stream. * * @returns VBox status code. * @param pCfgTokenizer The config tokenizer. */ static int autostartConfigTokenizerReadNextLine(PCFGTOKENIZER pCfgTokenizer) { int rc = VINF_SUCCESS; if (pCfgTokenizer->fEof) return VERR_EOF; do { rc = RTStrmGetLine(pCfgTokenizer->hStrmConfig, pCfgTokenizer->pszLine, pCfgTokenizer->cbLine); if (rc == VERR_BUFFER_OVERFLOW) { char *pszTmp; pCfgTokenizer->cbLine += 128; pszTmp = (char *)RTMemRealloc(pCfgTokenizer->pszLine, pCfgTokenizer->cbLine); if (pszTmp) pCfgTokenizer->pszLine = pszTmp; else rc = VERR_NO_MEMORY; } } while (rc == VERR_BUFFER_OVERFLOW); if ( RT_SUCCESS(rc) || rc == VERR_EOF) { pCfgTokenizer->iLine++; pCfgTokenizer->cchCurr = 1; pCfgTokenizer->pszLineCurr = pCfgTokenizer->pszLine; if (rc == VERR_EOF) pCfgTokenizer->fEof = true; } return rc; } /** * Get the next token from the config stream and create a token structure. * * @returns VBox status code. * @param pCfgTokenizer The config tokenizer data. * @param pCfgTokenUse Allocated token structure to use or NULL to allocate * a new one. It will bee freed if an error is encountered. * @param ppCfgToken Where to store the pointer to the next token on success. */ static int autostartConfigTokenizerCreateToken(PCFGTOKENIZER pCfgTokenizer, PCFGTOKEN pCfgTokenUse, PCFGTOKEN *ppCfgToken) { const char *pszToken = NULL; size_t cchToken = 1; size_t cchAdvance = 0; CFGTOKENTYPE enmType = CFGTOKENTYPE_INVALID; int rc = VINF_SUCCESS; for (;;) { pszToken = pCfgTokenizer->pszLineCurr; /* Skip all spaces. */ while (RT_C_IS_BLANK(*pszToken)) { pszToken++; cchAdvance++; } /* Check if we have to read a new line. */ if ( *pszToken == '\0' || *pszToken == '#') { rc = autostartConfigTokenizerReadNextLine(pCfgTokenizer); if (rc == VERR_EOF) { enmType = CFGTOKENTYPE_EOF; rc = VINF_SUCCESS; break; } else if (RT_FAILURE(rc)) break; /* start from the beginning. */ cchAdvance = 0; } else if (*pszToken == '=') { enmType = CFGTOKENTYPE_EQUAL; break; } else if (*pszToken == ',') { enmType = CFGTOKENTYPE_COMMA; break; } else if (*pszToken == '{') { enmType = CFGTOKENTYPE_CURLY_OPEN; break; } else if (*pszToken == '}') { enmType = CFGTOKENTYPE_CURLY_CLOSING; break; } else { const char *pszTmp = pszToken; cchToken = 0; enmType = CFGTOKENTYPE_ID; /* Get the complete token. */ while ( RT_C_IS_ALNUM(*pszTmp) || *pszTmp == '_' || *pszTmp == '.') { pszTmp++; cchToken++; } break; } } Assert(RT_FAILURE(rc) || enmType != CFGTOKENTYPE_INVALID); if (RT_SUCCESS(rc)) { /* Free the given token if it is an ID or the current one is an ID token. */ if ( pCfgTokenUse && ( pCfgTokenUse->enmType == CFGTOKENTYPE_ID || enmType == CFGTOKENTYPE_ID)) { autostartConfigTokenFree(pCfgTokenizer, pCfgTokenUse); pCfgTokenUse = NULL; } if (!pCfgTokenUse) { size_t cbToken = sizeof(CFGTOKEN); if (enmType == CFGTOKENTYPE_ID) cbToken += (cchToken + 1) * sizeof(char); pCfgTokenUse = (PCFGTOKEN)RTMemAllocZ(cbToken); if (!pCfgTokenUse) rc = VERR_NO_MEMORY; } if (RT_SUCCESS(rc)) { /* Copy token data. */ pCfgTokenUse->enmType = enmType; pCfgTokenUse->cchStart = pCfgTokenizer->cchCurr; pCfgTokenUse->iLine = pCfgTokenizer->iLine; if (enmType == CFGTOKENTYPE_ID) { pCfgTokenUse->u.Id.cchToken = cchToken; memcpy(pCfgTokenUse->u.Id.achToken, pszToken, cchToken); } } else if (pCfgTokenUse) autostartConfigTokenFree(pCfgTokenizer, pCfgTokenUse); if (RT_SUCCESS(rc)) { /* Set new position in config stream. */ pCfgTokenizer->pszLineCurr += cchToken + cchAdvance; pCfgTokenizer->cchCurr += cchToken + cchAdvance; *ppCfgToken = pCfgTokenUse; } } return rc; } /** * Destroys the given config tokenizer. * * @returns nothing. * @param pCfgTokenizer The config tokenizer to destroy. */ static void autostartConfigTokenizerDestroy(PCFGTOKENIZER pCfgTokenizer) { if (pCfgTokenizer->pszLine) RTMemFree(pCfgTokenizer->pszLine); if (pCfgTokenizer->hStrmConfig) RTStrmClose(pCfgTokenizer->hStrmConfig); if (pCfgTokenizer->pTokenNext) RTMemFree(pCfgTokenizer->pTokenNext); RTMemFree(pCfgTokenizer); } /** * Creates the config tokenizer from the given filename. * * @returns VBox status code. * @param pszFilename Config filename. * @param ppCfgTokenizer Where to store the pointer to the config tokenizer on * success. */ static int autostartConfigTokenizerCreate(const char *pszFilename, PCFGTOKENIZER *ppCfgTokenizer) { int rc = VINF_SUCCESS; PCFGTOKENIZER pCfgTokenizer = (PCFGTOKENIZER)RTMemAllocZ(sizeof(CFGTOKENIZER)); if (pCfgTokenizer) { pCfgTokenizer->iLine = 0; pCfgTokenizer->cbLine = 128; pCfgTokenizer->pszLine = (char *)RTMemAllocZ(pCfgTokenizer->cbLine); if (pCfgTokenizer->pszLine) { rc = RTStrmOpen(pszFilename, "r", &pCfgTokenizer->hStrmConfig); if (RT_SUCCESS(rc)) { rc = autostartConfigTokenizerReadNextLine(pCfgTokenizer); if (RT_SUCCESS(rc)) rc = autostartConfigTokenizerCreateToken(pCfgTokenizer, NULL, &pCfgTokenizer->pTokenNext); } } else rc = VERR_NO_MEMORY; } else rc = VERR_NO_MEMORY; if (RT_SUCCESS(rc)) *ppCfgTokenizer = pCfgTokenizer; else if ( RT_FAILURE(rc) && pCfgTokenizer) autostartConfigTokenizerDestroy(pCfgTokenizer); return rc; } /** * Return the next token from the config stream. * * @returns VBox status code. * @param pCfgTokenizer The config tokenizer. * @param ppCfgToken Where to store the next token. */ static int autostartConfigTokenizerGetNextToken(PCFGTOKENIZER pCfgTokenizer, PCFGTOKEN *ppCfgToken) { *ppCfgToken = pCfgTokenizer->pTokenNext; return autostartConfigTokenizerCreateToken(pCfgTokenizer, NULL, &pCfgTokenizer->pTokenNext); } /** * Returns a stringified version of the token type. * * @returns Stringified version of the token type. * @param enmType Token type. */ static const char *autostartConfigTokenTypeToStr(CFGTOKENTYPE enmType) { switch (enmType) { case CFGTOKENTYPE_COMMA: return ","; case CFGTOKENTYPE_EQUAL: return "="; case CFGTOKENTYPE_CURLY_OPEN: return "{"; case CFGTOKENTYPE_CURLY_CLOSING: return "}"; case CFGTOKENTYPE_EOF: return ""; case CFGTOKENTYPE_ID: return ""; default: AssertFailed(); return ""; } /* not reached */ } /** * Returns a stringified version of the token. * * @returns Stringified version of the token type. * @param pToken Token. */ static const char *autostartConfigTokenToString(PCFGTOKEN pToken) { if (pToken->enmType == CFGTOKENTYPE_ID) return pToken->u.Id.achToken; else return autostartConfigTokenTypeToStr(pToken->enmType); } /** * Returns the length of the token in characters (without zero terminator). * * @returns Token length. * @param pToken Token. */ static size_t autostartConfigTokenGetLength(PCFGTOKEN pToken) { switch (pToken->enmType) { case CFGTOKENTYPE_COMMA: case CFGTOKENTYPE_EQUAL: case CFGTOKENTYPE_CURLY_OPEN: case CFGTOKENTYPE_CURLY_CLOSING: return 1; case CFGTOKENTYPE_EOF: return 0; case CFGTOKENTYPE_ID: return strlen(pToken->u.Id.achToken); default: AssertFailed(); return 0; } /* not reached */ } /** * Log unexpected token error. * * @returns nothing. * @param pToken The token which caused the error. * @param pszExpected String of the token which was expected. */ static void autostartConfigTokenizerMsgUnexpectedToken(PCFGTOKEN pToken, const char *pszExpected) { autostartSvcLogError("Unexpected token '%s' at %d:%d.%d, expected '%s'", autostartConfigTokenToString(pToken), pToken->iLine, pToken->cchStart, pToken->cchStart + autostartConfigTokenGetLength(pToken) - 1, pszExpected); } /** * Verfies a token and consumes it. * * @returns VBox status code. * @param pCfgTokenizer The config tokenizer. * @param pszTokenCheck The token to check for. */ static int autostartConfigTokenizerCheckAndConsume(PCFGTOKENIZER pCfgTokenizer, CFGTOKENTYPE enmType) { int rc = VINF_SUCCESS; PCFGTOKEN pCfgToken = NULL; rc = autostartConfigTokenizerGetNextToken(pCfgTokenizer, &pCfgToken); if (RT_SUCCESS(rc)) { if (pCfgToken->enmType != enmType) { autostartConfigTokenizerMsgUnexpectedToken(pCfgToken, autostartConfigTokenTypeToStr(enmType)); rc = VERR_INVALID_PARAMETER; } autostartConfigTokenFree(pCfgTokenizer, pCfgToken); } return rc; } /** * Consumes the next token in the stream. * * @returns VBox status code. * @param pCfgTokenizer Tokenizer instance data. */ static int autostartConfigTokenizerConsume(PCFGTOKENIZER pCfgTokenizer) { int rc = VINF_SUCCESS; PCFGTOKEN pCfgToken = NULL; rc = autostartConfigTokenizerGetNextToken(pCfgTokenizer, &pCfgToken); if (RT_SUCCESS(rc)) autostartConfigTokenFree(pCfgTokenizer, pCfgToken); return rc; } /** * Returns the start of the next token without consuming it. * * @returns The next token without consuming it. * @param pCfgTokenizer Tokenizer instance data. */ DECLINLINE(PCFGTOKEN) autostartConfigTokenizerPeek(PCFGTOKENIZER pCfgTokenizer) { return pCfgTokenizer->pTokenNext; } /** * Check whether the next token is equal to the given one. * * @returns true if the next token in the stream is equal to the given one * false otherwise. * @param pszToken The token to check for. */ DECLINLINE(bool) autostartConfigTokenizerPeekIsEqual(PCFGTOKENIZER pCfgTokenizer, CFGTOKENTYPE enmType) { PCFGTOKEN pToken = autostartConfigTokenizerPeek(pCfgTokenizer); return pToken->enmType == enmType; } /** * Parse a key value node and returns the AST. * * @returns VBox status code. * @param pCfgTokenizer The tokenizer for the config stream. * @param pszKey The key for the pair. * @param ppCfgAst Where to store the resulting AST on success. */ static int autostartConfigParseValue(PCFGTOKENIZER pCfgTokenizer, const char *pszKey, PCFGAST *ppCfgAst) { int rc = VINF_SUCCESS; PCFGTOKEN pToken = NULL; rc = autostartConfigTokenizerGetNextToken(pCfgTokenizer, &pToken); if ( RT_SUCCESS(rc) && pToken->enmType == CFGTOKENTYPE_ID) { PCFGAST pCfgAst = NULL; pCfgAst = (PCFGAST)RTMemAllocZ(RT_OFFSETOF(CFGAST, u.KeyValue.aszValue[pToken->u.Id.cchToken + 1])); if (!pCfgAst) return VERR_NO_MEMORY; pCfgAst->enmType = CFGASTNODETYPE_KEYVALUE; pCfgAst->pszKey = RTStrDup(pszKey); if (!pCfgAst->pszKey) { RTMemFree(pCfgAst); return VERR_NO_MEMORY; } memcpy(pCfgAst->u.KeyValue.aszValue, pToken->u.Id.achToken, pToken->u.Id.cchToken); pCfgAst->u.KeyValue.cchValue = pToken->u.Id.cchToken; *ppCfgAst = pCfgAst; } else { autostartConfigTokenizerMsgUnexpectedToken(pToken, "non reserved token"); rc = VERR_INVALID_PARAMETER; } return rc; } /** * Parses a compound node constructing the AST and returning it on success. * * @returns VBox status code. * @param pCfgTokenizer The tokenizer for the config stream. * @param pszScopeId The scope ID of the compound node. * @param ppCfgAst Where to store the resulting AST on success. */ static int autostartConfigParseCompoundNode(PCFGTOKENIZER pCfgTokenizer, const char *pszScopeId, PCFGAST *ppCfgAst) { unsigned cAstNodesMax = 10; PCFGAST pCfgAst = (PCFGAST)RTMemAllocZ(RT_OFFSETOF(CFGAST, u.Compound.apAstNodes[cAstNodesMax])); if (!pCfgAst) return VERR_NO_MEMORY; pCfgAst->enmType = CFGASTNODETYPE_COMPOUND; pCfgAst->u.Compound.cAstNodes = 0; pCfgAst->pszKey = RTStrDup(pszScopeId); if (!pCfgAst->pszKey) { RTMemFree(pCfgAst); return VERR_NO_MEMORY; } int rc = VINF_SUCCESS; do { PCFGTOKEN pToken = NULL; PCFGAST pAstNode = NULL; if ( autostartConfigTokenizerPeekIsEqual(pCfgTokenizer, CFGTOKENTYPE_CURLY_CLOSING) || autostartConfigTokenizerPeekIsEqual(pCfgTokenizer, CFGTOKENTYPE_EOF)) break; rc = autostartConfigTokenizerGetNextToken(pCfgTokenizer, &pToken); if ( RT_SUCCESS(rc) && pToken->enmType == CFGTOKENTYPE_ID) { /* Next must be a = token in all cases at this place. */ rc = autostartConfigTokenizerCheckAndConsume(pCfgTokenizer, CFGTOKENTYPE_EQUAL); if (RT_SUCCESS(rc)) { /* Check whether this is a compound node. */ if (autostartConfigTokenizerPeekIsEqual(pCfgTokenizer, CFGTOKENTYPE_CURLY_OPEN)) { rc = autostartConfigTokenizerConsume(pCfgTokenizer); if (RT_SUCCESS(rc)) rc = autostartConfigParseCompoundNode(pCfgTokenizer, pToken->u.Id.achToken, &pAstNode); if (RT_SUCCESS(rc)) rc = autostartConfigTokenizerCheckAndConsume(pCfgTokenizer, CFGTOKENTYPE_CURLY_CLOSING); } else rc = autostartConfigParseValue(pCfgTokenizer, pToken->u.Id.achToken, &pAstNode); } } else if (RT_SUCCESS(rc)) { autostartConfigTokenizerMsgUnexpectedToken(pToken, "non reserved token"); rc = VERR_INVALID_PARAMETER; } /* Add to the current compound node. */ if (RT_SUCCESS(rc)) { if (pCfgAst->u.Compound.cAstNodes >= cAstNodesMax) { cAstNodesMax += 10; PCFGAST pCfgAstNew = (PCFGAST)RTMemRealloc(pCfgAst, RT_OFFSETOF(CFGAST, u.Compound.apAstNodes[cAstNodesMax])); if (!pCfgAstNew) rc = VERR_NO_MEMORY; else pCfgAst = pCfgAstNew; } if (RT_SUCCESS(rc)) { pCfgAst->u.Compound.apAstNodes[pCfgAst->u.Compound.cAstNodes] = pAstNode; pCfgAst->u.Compound.cAstNodes++; } } autostartConfigTokenFree(pCfgTokenizer, pToken); } while (RT_SUCCESS(rc)); if (RT_SUCCESS(rc)) *ppCfgAst = pCfgAst; else autostartConfigAstDestroy(pCfgAst); return rc; } DECLHIDDEN(int) autostartParseConfig(const char *pszFilename, PCFGAST *ppCfgAst) { PCFGTOKENIZER pCfgTokenizer = NULL; int rc = VINF_SUCCESS; PCFGAST pCfgAst = NULL; AssertPtrReturn(pszFilename, VERR_INVALID_POINTER); AssertPtrReturn(ppCfgAst, VERR_INVALID_POINTER); rc = autostartConfigTokenizerCreate(pszFilename, &pCfgTokenizer); if (RT_SUCCESS(rc)) { rc = autostartConfigParseCompoundNode(pCfgTokenizer, "", &pCfgAst); if (RT_SUCCESS(rc)) rc = autostartConfigTokenizerCheckAndConsume(pCfgTokenizer, CFGTOKENTYPE_EOF); } if (pCfgTokenizer) autostartConfigTokenizerDestroy(pCfgTokenizer); if (RT_SUCCESS(rc)) *ppCfgAst = pCfgAst; return rc; } DECLHIDDEN(void) autostartConfigAstDestroy(PCFGAST pCfgAst) { AssertPtrReturnVoid(pCfgAst); switch (pCfgAst->enmType) { case CFGASTNODETYPE_KEYVALUE: { RTMemFree(pCfgAst); break; } case CFGASTNODETYPE_COMPOUND: { for (unsigned i = 0; i < pCfgAst->u.Compound.cAstNodes; i++) autostartConfigAstDestroy(pCfgAst->u.Compound.apAstNodes[i]); RTMemFree(pCfgAst); break; } case CFGASTNODETYPE_LIST: default: AssertMsgFailed(("Invalid AST node type %d\n", pCfgAst->enmType)); } } DECLHIDDEN(PCFGAST) autostartConfigAstGetByName(PCFGAST pCfgAst, const char *pszName) { if (!pCfgAst) return NULL; AssertReturn(pCfgAst->enmType == CFGASTNODETYPE_COMPOUND, NULL); for (unsigned i = 0; i < pCfgAst->u.Compound.cAstNodes; i++) { PCFGAST pNode = pCfgAst->u.Compound.apAstNodes[i]; if (!RTStrCmp(pNode->pszKey, pszName)) return pNode; } return NULL; }