/*
* parseForProtos()
*
* Input: filein (output of cpp)
* prestring (<optional> string that prefaces each decl;
* use NULL to omit)
* Return: parsestr (string of function prototypes), or NULL on error
*
* Notes:
* (1) We parse the output of cpp:
* cpp -ansi <filein>
* Three plans were attempted, with success on the third.
* (2) Plan 1. A cursory examination of the cpp output indicated that
* every function was preceeded by a cpp comment statement.
* So we just need to look at statements beginning after comments.
* Unfortunately, this is NOT the case. Some functions start
* without cpp comment lines, typically when there are no
* comments in the source that immediately precede the function.
* (3) Plan 2. Consider the keywords in the language that start
* parts of the cpp file. Some, like 'typedef', 'enum',
* 'union' and 'struct', are followed after a while by '{',
* and eventually end with '}, plus an optional token and a
* final ';' Others, like 'extern' and 'static', are never
* the beginnings of global function definitions. Function
* prototypes have one or more sets of '(' followed eventually
* by a ')', and end with ';'. But function definitions have
* tokens, followed by '(', more tokens, ')' and then
* immediately a '{'. We would generate a prototype from this
* by adding a ';' to all tokens up to the ')'. So we use
* these special tokens to decide what we are parsing. And
* whenever a function definition is found and the prototype
* extracted, we skip through the rest of the function
* past the corresponding '}'. This token ends a line, and
* is often on a line of its own. But as it turns out,
* the only keyword we need to consider is 'static'.
* (4) Plan 3. Consider the parentheses and braces for various
* declarations. A struct, enum, or union has a pair of
* braces followed by a semicolon. They cannot have parentheses
* before the left brace, but a struct can have lots of parentheses
* within the brace set. A function prototype has no braces.
* A function declaration can have sets of left and right
* parentheses, but these are followed by a left brace.
* So plan 3 looks at the way parentheses and braces are
* organized. Once the beginning of a function definition
* is found, the prototype is extracted and we search for
* the ending right brace.
* (5) To find the ending right brace, it is necessary to do some
* careful parsing. For example, in this file, we have
* left and right braces as characters, and these must not
* be counted. Somewhat more tricky, the file fhmtauto.c
* generates code, and includes a right brace in a string.
* So we must not include braces that are in strings. But how
* do we know if something is inside a string? Keep state,
* starting with not-inside, and every time you hit a double quote
* that is not escaped, toggle the condition. Any brace
* found in the state of being within a string is ignored.
* (6) When a prototype is extracted, it is put in a canonical
* form (i.e., cleaned up). Finally, we check that it is
* not static and save it. (If static, it is ignored).
* (7) The @prestring for unix is NULL; it is included here so that
* you can use Microsoft's declaration for importing or
* exporting to a dll. See environ.h for examples of use.
* Here, we set: @prestring = "LEPT_DLL ". Note in particular
* the space character that will separate 'LEPT_DLL' from
* the standard unix prototype that follows.
*/
char *
parseForProtos(const char *filein,
const char *prestring)
{
char *strdata, *str, *newstr, *parsestr, *secondword;
l_int32 nbytes, start, next, stop, charindex, found;
SARRAY *sa, *saout, *satest;
PROCNAME("parseForProtos");
if (!filein)
return (char *)ERROR_PTR("filein not defined", procName, NULL);
/* Read in the cpp output into memory, one string for each
* line in the file, omitting blank lines. */
strdata = (char *)arrayRead(filein, &nbytes);
sa = sarrayCreateLinesFromString(strdata, 0);
saout = sarrayCreate(0);
next = 0;
while (1) { /* repeat after each non-static prototype is extracted */
searchForProtoSignature(sa, next, &start, &stop, &charindex, &found);
if (!found)
break;
/* fprintf(stderr, " start = %d, stop = %d, charindex = %d\n",
start, stop, charindex); */
str = captureProtoSignature(sa, start, stop, charindex);
/* Make sure it is not static. Note that 'extern' has
* been prepended to the prototype, so the 'static'
* keyword, if it exists, would be the second word. */
satest = sarrayCreateWordsFromString(str);
secondword = sarrayGetString(satest, 1, 0);
if (strcmp(secondword, "static")) { /* not static */
if (prestring) { /* prepend it to the prototype */
newstr = stringJoin(prestring, str);
sarrayAddString(saout, newstr, L_INSERT);
FREE(str);
}
else
sarrayAddString(saout, str, L_INSERT);
}
else
FREE(str);
sarrayDestroy(&satest);
skipToEndOfFunction(sa, stop, charindex, &next);
if (next == -1) break;
}
/* Flatten into a string with newlines between prototypes */
parsestr = sarrayToString(saout, 1);
FREE(strdata);
sarrayDestroy(&sa);
sarrayDestroy(&saout);
return parsestr;
}
/*
* parseForProtos()
*
* Input: filein (output of cpp)
* prestring (<optional> string that prefaces each decl;
* use NULL to omit)
* Return: parsestr (string of function prototypes), or NULL on error
*
* Notes:
* (1) We parse the output of cpp:
* cpp -ansi <filein>
* Three plans were attempted, with success on the third.
* (2) Plan 1. A cursory examination of the cpp output indicated that
* every function was preceded by a cpp comment statement.
* So we just need to look at statements beginning after comments.
* Unfortunately, this is NOT the case. Some functions start
* without cpp comment lines, typically when there are no
* comments in the source that immediately precede the function.
* (3) Plan 2. Consider the keywords in the language that start
* parts of the cpp file. Some, like 'typedef', 'enum',
* 'union' and 'struct', are followed after a while by '{',
* and eventually end with '}, plus an optional token and a
* final ';' Others, like 'extern' and 'static', are never
* the beginnings of global function definitions. Function
* prototypes have one or more sets of '(' followed eventually
* by a ')', and end with ';'. But function definitions have
* tokens, followed by '(', more tokens, ')' and then
* immediately a '{'. We would generate a prototype from this
* by adding a ';' to all tokens up to the ')'. So we use
* these special tokens to decide what we are parsing. And
* whenever a function definition is found and the prototype
* extracted, we skip through the rest of the function
* past the corresponding '}'. This token ends a line, and
* is often on a line of its own. But as it turns out,
* the only keyword we need to consider is 'static'.
* (4) Plan 3. Consider the parentheses and braces for various
* declarations. A struct, enum, or union has a pair of
* braces followed by a semicolon. They cannot have parentheses
* before the left brace, but a struct can have lots of parentheses
* within the brace set. A function prototype has no braces.
* A function declaration can have sets of left and right
* parentheses, but these are followed by a left brace.
* So plan 3 looks at the way parentheses and braces are
* organized. Once the beginning of a function definition
* is found, the prototype is extracted and we search for
* the ending right brace.
* (5) To find the ending right brace, it is necessary to do some
* careful parsing. For example, in this file, we have
* left and right braces as characters, and these must not
* be counted. Somewhat more tricky, the file fhmtauto.c
* generates code, and includes a right brace in a string.
* So we must not include braces that are in strings. But how
* do we know if something is inside a string? Keep state,
* starting with not-inside, and every time you hit a double quote
* that is not escaped, toggle the condition. Any brace
* found in the state of being within a string is ignored.
* (6) When a prototype is extracted, it is put in a canonical
* form (i.e., cleaned up). Finally, we check that it is
* not static and save it. (If static, it is ignored).
* (7) The @prestring for unix is NULL; it is included here so that
* you can use Microsoft's declaration for importing or
* exporting to a dll. See environ.h for examples of use.
* Here, we set: @prestring = "LEPT_DLL ". Note in particular
* the space character that will separate 'LEPT_DLL' from
* the standard unix prototype that follows.
*/
char *
parseForProtos(const char *filein,
const char *prestring)
{
char *strdata, *str, *newstr, *parsestr, *secondword;
l_int32 start, next, stop, charindex, found;
size_t nbytes;
SARRAY *sa, *saout, *satest;
PROCNAME("parseForProtos");
if (!filein)
return (char *)ERROR_PTR("filein not defined", procName, NULL);
/* Read in the cpp output into memory, one string for each
* line in the file, omitting blank lines. */
strdata = (char *)l_binaryRead(filein, &nbytes);
sa = sarrayCreateLinesFromString(strdata, 0);
saout = sarrayCreate(0);
next = 0;
while (1) { /* repeat after each non-static prototype is extracted */
searchForProtoSignature(sa, next, &start, &stop, &charindex, &found);
if (!found)
break;
/* fprintf(stderr, " start = %d, stop = %d, charindex = %d\n",
start, stop, charindex); */
str = captureProtoSignature(sa, start, stop, charindex);
/* Make sure that the signature found by cpp is neither
* static nor extern. We get 'extern' declarations from
* header files, and with some versions of cpp running on
* #include <sys/stat.h> we get something of the form:
* extern ... (( ... )) ... ( ... ) { ...
* For this, the 1st '(' is the lp, the 2nd ')' is the rp,
* and there is a lot of garbage between the rp and the lb.
* It is easiest to simply reject any signature that starts
* with 'extern'. Note also that an 'extern' token has been
* prepended to each prototype, so the 'static' or
* 'extern' keywords we are looking for, if they exist,
* would be the second word. */
satest = sarrayCreateWordsFromString(str);
secondword = sarrayGetString(satest, 1, L_NOCOPY);
if (strcmp(secondword, "static") && /* not static */
strcmp(secondword, "extern")) { /* not extern */
if (prestring) { /* prepend it to the prototype */
newstr = stringJoin(prestring, str);
sarrayAddString(saout, newstr, L_INSERT);
LEPT_FREE(str);
} else {
sarrayAddString(saout, str, L_INSERT);
}
} else {
LEPT_FREE(str);
}
sarrayDestroy(&satest);
skipToEndOfFunction(sa, stop, charindex, &next);
if (next == -1) break;
}
/* Flatten into a string with newlines between prototypes */
parsestr = sarrayToString(saout, 1);
LEPT_FREE(strdata);
sarrayDestroy(&sa);
sarrayDestroy(&saout);
return parsestr;
}
