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-rw-r--r--modules/libpref/prefread.cpp657
1 files changed, 657 insertions, 0 deletions
diff --git a/modules/libpref/prefread.cpp b/modules/libpref/prefread.cpp
new file mode 100644
index 000000000..605dcaac6
--- /dev/null
+++ b/modules/libpref/prefread.cpp
@@ -0,0 +1,657 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include "prefread.h"
+#include "nsString.h"
+#include "nsUTF8Utils.h"
+
+#ifdef TEST_PREFREAD
+#include <stdio.h>
+#define NS_WARNING(_s) printf(">>> " _s "!\n")
+#define NS_NOTREACHED(_s) NS_WARNING(_s)
+#else
+#include "nsDebug.h" // for NS_WARNING
+#endif
+
+/* pref parser states */
+enum {
+ PREF_PARSE_INIT,
+ PREF_PARSE_MATCH_STRING,
+ PREF_PARSE_UNTIL_NAME,
+ PREF_PARSE_QUOTED_STRING,
+ PREF_PARSE_UNTIL_COMMA,
+ PREF_PARSE_UNTIL_VALUE,
+ PREF_PARSE_INT_VALUE,
+ PREF_PARSE_COMMENT_MAYBE_START,
+ PREF_PARSE_COMMENT_BLOCK,
+ PREF_PARSE_COMMENT_BLOCK_MAYBE_END,
+ PREF_PARSE_ESC_SEQUENCE,
+ PREF_PARSE_HEX_ESCAPE,
+ PREF_PARSE_UTF16_LOW_SURROGATE,
+ PREF_PARSE_UNTIL_OPEN_PAREN,
+ PREF_PARSE_UNTIL_CLOSE_PAREN,
+ PREF_PARSE_UNTIL_SEMICOLON,
+ PREF_PARSE_UNTIL_EOL
+};
+
+#define UTF16_ESC_NUM_DIGITS 4
+#define HEX_ESC_NUM_DIGITS 2
+#define BITS_PER_HEX_DIGIT 4
+
+static const char kUserPref[] = "user_pref";
+static const char kPref[] = "pref";
+static const char kPrefSticky[] = "sticky_pref";
+static const char kTrue[] = "true";
+static const char kFalse[] = "false";
+
+/**
+ * pref_GrowBuf
+ *
+ * this function will increase the size of the buffer owned
+ * by the given pref parse state. We currently use a simple
+ * doubling algorithm, but the only hard requirement is that
+ * it increase the buffer by at least the size of the ps->esctmp
+ * buffer used for escape processing (currently 6 bytes).
+ *
+ * this buffer is used to store partial pref lines. it is
+ * freed when the parse state is destroyed.
+ *
+ * @param ps
+ * parse state instance
+ *
+ * this function updates all pointers that reference an
+ * address within lb since realloc may relocate the buffer.
+ *
+ * @return false if insufficient memory.
+ */
+static bool
+pref_GrowBuf(PrefParseState *ps)
+{
+ int bufLen, curPos, valPos;
+
+ bufLen = ps->lbend - ps->lb;
+ curPos = ps->lbcur - ps->lb;
+ valPos = ps->vb - ps->lb;
+
+ if (bufLen == 0)
+ bufLen = 128; /* default buffer size */
+ else
+ bufLen <<= 1; /* double buffer size */
+
+#ifdef TEST_PREFREAD
+ fprintf(stderr, ">>> realloc(%d)\n", bufLen);
+#endif
+
+ ps->lb = (char*) realloc(ps->lb, bufLen);
+ if (!ps->lb)
+ return false;
+
+ ps->lbcur = ps->lb + curPos;
+ ps->lbend = ps->lb + bufLen;
+ ps->vb = ps->lb + valPos;
+
+ return true;
+}
+
+/**
+ * Report an error or a warning. If not specified, just dump to stderr.
+ */
+static void
+pref_ReportParseProblem(PrefParseState& ps, const char* aMessage, int aLine, bool aError)
+{
+ if (ps.reporter) {
+ ps.reporter(aMessage, aLine, aError);
+ } else {
+ printf_stderr("**** Preference parsing %s (line %d) = %s **\n",
+ (aError ? "error" : "warning"), aLine, aMessage);
+ }
+}
+
+/**
+ * pref_DoCallback
+ *
+ * this function is called when a complete pref name-value pair has
+ * been extracted from the input data.
+ *
+ * @param ps
+ * parse state instance
+ *
+ * @return false to indicate a fatal error.
+ */
+static bool
+pref_DoCallback(PrefParseState *ps)
+{
+ PrefValue value;
+
+ switch (ps->vtype) {
+ case PrefType::String:
+ value.stringVal = ps->vb;
+ break;
+ case PrefType::Int:
+ if ((ps->vb[0] == '-' || ps->vb[0] == '+') && ps->vb[1] == '\0') {
+ pref_ReportParseProblem(*ps, "invalid integer value", 0, true);
+ NS_WARNING("malformed integer value");
+ return false;
+ }
+ value.intVal = atoi(ps->vb);
+ break;
+ case PrefType::Bool:
+ value.boolVal = (ps->vb == kTrue);
+ break;
+ default:
+ break;
+ }
+ (*ps->reader)(ps->closure, ps->lb, value, ps->vtype, ps->fdefault,
+ ps->fstickydefault);
+ return true;
+}
+
+void
+PREF_InitParseState(PrefParseState *ps, PrefReader reader,
+ PrefParseErrorReporter reporter, void *closure)
+{
+ memset(ps, 0, sizeof(*ps));
+ ps->reader = reader;
+ ps->closure = closure;
+ ps->reporter = reporter;
+}
+
+void
+PREF_FinalizeParseState(PrefParseState *ps)
+{
+ if (ps->lb)
+ free(ps->lb);
+}
+
+/**
+ * Pseudo-BNF
+ * ----------
+ * function = LJUNK function-name JUNK function-args
+ * function-name = "user_pref" | "pref" | "sticky_pref"
+ * function-args = "(" JUNK pref-name JUNK "," JUNK pref-value JUNK ")" JUNK ";"
+ * pref-name = quoted-string
+ * pref-value = quoted-string | "true" | "false" | integer-value
+ * JUNK = *(WS | comment-block | comment-line)
+ * LJUNK = *(WS | comment-block | comment-line | bcomment-line)
+ * WS = SP | HT | LF | VT | FF | CR
+ * SP = <US-ASCII SP, space (32)>
+ * HT = <US-ASCII HT, horizontal-tab (9)>
+ * LF = <US-ASCII LF, linefeed (10)>
+ * VT = <US-ASCII HT, vertical-tab (11)>
+ * FF = <US-ASCII FF, form-feed (12)>
+ * CR = <US-ASCII CR, carriage return (13)>
+ * comment-block = <C/C++ style comment block>
+ * comment-line = <C++ style comment line>
+ * bcomment-line = <bourne-shell style comment line>
+ */
+bool
+PREF_ParseBuf(PrefParseState *ps, const char *buf, int bufLen)
+{
+ const char *end;
+ char c;
+ char udigit;
+ int state;
+
+ // The line number is currently only used for the error/warning reporting.
+ int lineNum = 0;
+
+ state = ps->state;
+ for (end = buf + bufLen; buf != end; ++buf) {
+ c = *buf;
+ if (c == '\r' || c == '\n' || c == 0x1A) {
+ lineNum ++;
+ }
+
+ switch (state) {
+ /* initial state */
+ case PREF_PARSE_INIT:
+ if (ps->lbcur != ps->lb) { /* reset state */
+ ps->lbcur = ps->lb;
+ ps->vb = nullptr;
+ ps->vtype = PrefType::Invalid;
+ ps->fdefault = false;
+ ps->fstickydefault = false;
+ }
+ switch (c) {
+ case '/': /* begin comment block or line? */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ break;
+ case '#': /* accept shell style comments */
+ state = PREF_PARSE_UNTIL_EOL;
+ break;
+ case 'u': /* indicating user_pref */
+ case 's': /* indicating sticky_pref */
+ case 'p': /* indicating pref */
+ if (c == 'u') {
+ ps->smatch = kUserPref;
+ } else if (c == 's') {
+ ps->smatch = kPrefSticky;
+ } else {
+ ps->smatch = kPref;
+ }
+ ps->sindex = 1;
+ ps->nextstate = PREF_PARSE_UNTIL_OPEN_PAREN;
+ state = PREF_PARSE_MATCH_STRING;
+ break;
+ /* else skip char */
+ }
+ break;
+
+ /* string matching */
+ case PREF_PARSE_MATCH_STRING:
+ if (c == ps->smatch[ps->sindex++]) {
+ /* if we've matched all characters, then move to next state. */
+ if (ps->smatch[ps->sindex] == '\0') {
+ state = ps->nextstate;
+ ps->nextstate = PREF_PARSE_INIT; /* reset next state */
+ }
+ /* else wait for next char */
+ }
+ else {
+ pref_ReportParseProblem(*ps, "non-matching string", lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+
+ /* quoted string parsing */
+ case PREF_PARSE_QUOTED_STRING:
+ /* we assume that the initial quote has already been consumed */
+ if (ps->lbcur == ps->lbend && !pref_GrowBuf(ps))
+ return false; /* out of memory */
+ if (c == '\\')
+ state = PREF_PARSE_ESC_SEQUENCE;
+ else if (c == ps->quotechar) {
+ *ps->lbcur++ = '\0';
+ state = ps->nextstate;
+ ps->nextstate = PREF_PARSE_INIT; /* reset next state */
+ }
+ else
+ *ps->lbcur++ = c;
+ break;
+
+ /* name parsing */
+ case PREF_PARSE_UNTIL_NAME:
+ if (c == '\"' || c == '\'') {
+ ps->fdefault = (ps->smatch == kPref || ps->smatch == kPrefSticky);
+ ps->fstickydefault = (ps->smatch == kPrefSticky);
+ ps->quotechar = c;
+ ps->nextstate = PREF_PARSE_UNTIL_COMMA; /* return here when done */
+ state = PREF_PARSE_QUOTED_STRING;
+ }
+ else if (c == '/') { /* allow embedded comment */
+ ps->nextstate = state; /* return here when done with comment */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ }
+ else if (!isspace(c)) {
+ pref_ReportParseProblem(*ps, "need space, comment or quote", lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+
+ /* parse until we find a comma separating name and value */
+ case PREF_PARSE_UNTIL_COMMA:
+ if (c == ',') {
+ ps->vb = ps->lbcur;
+ state = PREF_PARSE_UNTIL_VALUE;
+ }
+ else if (c == '/') { /* allow embedded comment */
+ ps->nextstate = state; /* return here when done with comment */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ }
+ else if (!isspace(c)) {
+ pref_ReportParseProblem(*ps, "need space, comment or comma", lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+
+ /* value parsing */
+ case PREF_PARSE_UNTIL_VALUE:
+ /* the pref value type is unknown. so, we scan for the first
+ * character of the value, and determine the type from that. */
+ if (c == '\"' || c == '\'') {
+ ps->vtype = PrefType::String;
+ ps->quotechar = c;
+ ps->nextstate = PREF_PARSE_UNTIL_CLOSE_PAREN;
+ state = PREF_PARSE_QUOTED_STRING;
+ }
+ else if (c == 't' || c == 'f') {
+ ps->vb = (char *) (c == 't' ? kTrue : kFalse);
+ ps->vtype = PrefType::Bool;
+ ps->smatch = ps->vb;
+ ps->sindex = 1;
+ ps->nextstate = PREF_PARSE_UNTIL_CLOSE_PAREN;
+ state = PREF_PARSE_MATCH_STRING;
+ }
+ else if (isdigit(c) || (c == '-') || (c == '+')) {
+ ps->vtype = PrefType::Int;
+ /* write c to line buffer... */
+ if (ps->lbcur == ps->lbend && !pref_GrowBuf(ps))
+ return false; /* out of memory */
+ *ps->lbcur++ = c;
+ state = PREF_PARSE_INT_VALUE;
+ }
+ else if (c == '/') { /* allow embedded comment */
+ ps->nextstate = state; /* return here when done with comment */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ }
+ else if (!isspace(c)) {
+ pref_ReportParseProblem(*ps, "need value, comment or space", lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+ case PREF_PARSE_INT_VALUE:
+ /* grow line buffer if necessary... */
+ if (ps->lbcur == ps->lbend && !pref_GrowBuf(ps))
+ return false; /* out of memory */
+ if (isdigit(c))
+ *ps->lbcur++ = c;
+ else {
+ *ps->lbcur++ = '\0'; /* stomp null terminator; we are done. */
+ if (c == ')')
+ state = PREF_PARSE_UNTIL_SEMICOLON;
+ else if (c == '/') { /* allow embedded comment */
+ ps->nextstate = PREF_PARSE_UNTIL_CLOSE_PAREN;
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ }
+ else if (isspace(c))
+ state = PREF_PARSE_UNTIL_CLOSE_PAREN;
+ else {
+ pref_ReportParseProblem(*ps, "while parsing integer", lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ }
+ break;
+
+ /* comment parsing */
+ case PREF_PARSE_COMMENT_MAYBE_START:
+ switch (c) {
+ case '*': /* comment block */
+ state = PREF_PARSE_COMMENT_BLOCK;
+ break;
+ case '/': /* comment line */
+ state = PREF_PARSE_UNTIL_EOL;
+ break;
+ default:
+ /* pref file is malformed */
+ pref_ReportParseProblem(*ps, "while parsing comment", lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+ case PREF_PARSE_COMMENT_BLOCK:
+ if (c == '*')
+ state = PREF_PARSE_COMMENT_BLOCK_MAYBE_END;
+ break;
+ case PREF_PARSE_COMMENT_BLOCK_MAYBE_END:
+ switch (c) {
+ case '/':
+ state = ps->nextstate;
+ ps->nextstate = PREF_PARSE_INIT;
+ break;
+ case '*': /* stay in this state */
+ break;
+ default:
+ state = PREF_PARSE_COMMENT_BLOCK;
+ }
+ break;
+
+ /* string escape sequence parsing */
+ case PREF_PARSE_ESC_SEQUENCE:
+ /* not necessary to resize buffer here since we should be writing
+ * only one character and the resize check would have been done
+ * for us in the previous state */
+ switch (c) {
+ case '\"':
+ case '\'':
+ case '\\':
+ break;
+ case 'r':
+ c = '\r';
+ break;
+ case 'n':
+ c = '\n';
+ break;
+ case 'x': /* hex escape -- always interpreted as Latin-1 */
+ case 'u': /* UTF16 escape */
+ ps->esctmp[0] = c;
+ ps->esclen = 1;
+ ps->utf16[0] = ps->utf16[1] = 0;
+ ps->sindex = (c == 'x' ) ?
+ HEX_ESC_NUM_DIGITS :
+ UTF16_ESC_NUM_DIGITS;
+ state = PREF_PARSE_HEX_ESCAPE;
+ continue;
+ default:
+ pref_ReportParseProblem(*ps, "preserving unexpected JS escape sequence",
+ lineNum, false);
+ NS_WARNING("preserving unexpected JS escape sequence");
+ /* Invalid escape sequence so we do have to write more than
+ * one character. Grow line buffer if necessary... */
+ if ((ps->lbcur+1) == ps->lbend && !pref_GrowBuf(ps))
+ return false; /* out of memory */
+ *ps->lbcur++ = '\\'; /* preserve the escape sequence */
+ break;
+ }
+ *ps->lbcur++ = c;
+ state = PREF_PARSE_QUOTED_STRING;
+ break;
+
+ /* parsing a hex (\xHH) or utf16 escape (\uHHHH) */
+ case PREF_PARSE_HEX_ESCAPE:
+ if ( c >= '0' && c <= '9' )
+ udigit = (c - '0');
+ else if ( c >= 'A' && c <= 'F' )
+ udigit = (c - 'A') + 10;
+ else if ( c >= 'a' && c <= 'f' )
+ udigit = (c - 'a') + 10;
+ else {
+ /* bad escape sequence found, write out broken escape as-is */
+ pref_ReportParseProblem(*ps, "preserving invalid or incomplete hex escape",
+ lineNum, false);
+ NS_WARNING("preserving invalid or incomplete hex escape");
+ *ps->lbcur++ = '\\'; /* original escape slash */
+ if ((ps->lbcur + ps->esclen) >= ps->lbend && !pref_GrowBuf(ps))
+ return false;
+ for (int i = 0; i < ps->esclen; ++i)
+ *ps->lbcur++ = ps->esctmp[i];
+
+ /* push the non-hex character back for re-parsing. */
+ /* (++buf at the top of the loop keeps this safe) */
+ --buf;
+ state = PREF_PARSE_QUOTED_STRING;
+ continue;
+ }
+
+ /* have a digit */
+ ps->esctmp[ps->esclen++] = c; /* preserve it */
+ ps->utf16[1] <<= BITS_PER_HEX_DIGIT;
+ ps->utf16[1] |= udigit;
+ ps->sindex--;
+ if (ps->sindex == 0) {
+ /* have the full escape. Convert to UTF8 */
+ int utf16len = 0;
+ if (ps->utf16[0]) {
+ /* already have a high surrogate, this is a two char seq */
+ utf16len = 2;
+ }
+ else if (0xD800 == (0xFC00 & ps->utf16[1])) {
+ /* a high surrogate, can't convert until we have the low */
+ ps->utf16[0] = ps->utf16[1];
+ ps->utf16[1] = 0;
+ state = PREF_PARSE_UTF16_LOW_SURROGATE;
+ break;
+ }
+ else {
+ /* a single utf16 character */
+ ps->utf16[0] = ps->utf16[1];
+ utf16len = 1;
+ }
+
+ /* actual conversion */
+ /* make sure there's room, 6 bytes is max utf8 len (in */
+ /* theory; 4 bytes covers the actual utf16 range) */
+ if (ps->lbcur+6 >= ps->lbend && !pref_GrowBuf(ps))
+ return false;
+
+ ConvertUTF16toUTF8 converter(ps->lbcur);
+ converter.write(ps->utf16, utf16len);
+ ps->lbcur += converter.Size();
+ state = PREF_PARSE_QUOTED_STRING;
+ }
+ break;
+
+ /* looking for beginning of utf16 low surrogate */
+ case PREF_PARSE_UTF16_LOW_SURROGATE:
+ if (ps->sindex == 0 && c == '\\') {
+ ++ps->sindex;
+ }
+ else if (ps->sindex == 1 && c == 'u') {
+ /* escape sequence is correct, now parse hex */
+ ps->sindex = UTF16_ESC_NUM_DIGITS;
+ ps->esctmp[0] = 'u';
+ ps->esclen = 1;
+ state = PREF_PARSE_HEX_ESCAPE;
+ }
+ else {
+ /* didn't find expected low surrogate. Ignore high surrogate
+ * (it would just get converted to nothing anyway) and start
+ * over with this character */
+ --buf;
+ if (ps->sindex == 1)
+ state = PREF_PARSE_ESC_SEQUENCE;
+ else
+ state = PREF_PARSE_QUOTED_STRING;
+ continue;
+ }
+ break;
+
+ /* function open and close parsing */
+ case PREF_PARSE_UNTIL_OPEN_PAREN:
+ /* tolerate only whitespace and embedded comments */
+ if (c == '(')
+ state = PREF_PARSE_UNTIL_NAME;
+ else if (c == '/') {
+ ps->nextstate = state; /* return here when done with comment */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ }
+ else if (!isspace(c)) {
+ pref_ReportParseProblem(*ps, "need space, comment or open parentheses",
+ lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+ case PREF_PARSE_UNTIL_CLOSE_PAREN:
+ /* tolerate only whitespace and embedded comments */
+ if (c == ')') {
+ state = PREF_PARSE_UNTIL_SEMICOLON;
+ } else if (c == '/') {
+ ps->nextstate = state; /* return here when done with comment */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ } else if (!isspace(c)) {
+ pref_ReportParseProblem(*ps, "need space, comment or closing parentheses",
+ lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+
+ /* function terminator ';' parsing */
+ case PREF_PARSE_UNTIL_SEMICOLON:
+ /* tolerate only whitespace and embedded comments */
+ if (c == ';') {
+ if (!pref_DoCallback(ps))
+ return false;
+ state = PREF_PARSE_INIT;
+ }
+ else if (c == '/') {
+ ps->nextstate = state; /* return here when done with comment */
+ state = PREF_PARSE_COMMENT_MAYBE_START;
+ }
+ else if (!isspace(c)) {
+ pref_ReportParseProblem(*ps, "need space, comment or semicolon",
+ lineNum, true);
+ NS_WARNING("malformed pref file");
+ return false;
+ }
+ break;
+
+ /* eol parsing */
+ case PREF_PARSE_UNTIL_EOL:
+ /* need to handle mac, unix, or dos line endings.
+ * PREF_PARSE_INIT will eat the next \n in case
+ * we have \r\n. */
+ if (c == '\r' || c == '\n' || c == 0x1A) {
+ state = ps->nextstate;
+ ps->nextstate = PREF_PARSE_INIT; /* reset next state */
+ }
+ break;
+ }
+ }
+ ps->state = state;
+ return true;
+}
+
+#ifdef TEST_PREFREAD
+
+static void
+pref_reader(void *closure,
+ const char *pref,
+ PrefValue val,
+ PrefType type,
+ bool defPref)
+{
+ printf("%spref(\"%s\", ", defPref ? "" : "user_", pref);
+ switch (type) {
+ case PREF_STRING:
+ printf("\"%s\");\n", val.stringVal);
+ break;
+ case PREF_INT:
+ printf("%i);\n", val.intVal);
+ break;
+ case PREF_BOOL:
+ printf("%s);\n", val.boolVal == false ? "false" : "true");
+ break;
+ }
+}
+
+int
+main(int argc, char **argv)
+{
+ PrefParseState ps;
+ char buf[4096]; /* i/o buffer */
+ FILE *fp;
+ int n;
+
+ if (argc == 1) {
+ printf("usage: prefread file.js\n");
+ return -1;
+ }
+
+ fp = fopen(argv[1], "r");
+ if (!fp) {
+ printf("failed to open file\n");
+ return -1;
+ }
+
+ PREF_InitParseState(&ps, pref_reader, nullptr, nullptr);
+
+ while ((n = fread(buf, 1, sizeof(buf), fp)) > 0)
+ PREF_ParseBuf(&ps, buf, n);
+
+ PREF_FinalizeParseState(&ps);
+
+ fclose(fp);
+ return 0;
+}
+
+#endif /* TEST_PREFREAD */
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