netcdf-c/oc/ocuri.c
2011-10-26 19:18:09 +00:00

690 lines
16 KiB
C

/*********************************************************************
* Copyright 2010, UCAR/Unidata
* See netcdf/COPYRIGHT file for copying and redistribution conditions.
* $Header$
*********************************************************************/
#include "config.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "ocuri.h"
#define OCURIDEBUG
#define LBRACKET '['
#define RBRACKET ']'
#ifndef FIX
#define FIX(s) ((s)==NULL?"":(s))
#endif
#ifndef NILLEN
#define NILLEN(s) ((s)==NULL?0:strlen(s))
#endif
#ifndef nulldup
#define nulldup(s) ((s)==NULL?NULL:strdup(s))
#endif
#ifndef HAVE_STRDUP
static char* nulldup(char* s)
{
char* dup = NULL;
if(s != NULL) {
dup = (char*)malloc(strlen(s)+1);
if(dup != NULL)
strcpy(dup,s);
}
return dup;
}
#endif
static char* legalprotocols[] = {
"file:",
"http:",
"https:",
"ftp:",
NULL /* NULL terminate*/
};
/* Allowable character sets for encode */
static char* fileallow =
"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!#$&'()*+,-./:;=?@_~";
static char* queryallow =
"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!#$&'()*+,-./:;=?@_~";
static void ocparamfree(char** params);
static int ocfind(char** params, const char* key);
/* Do a simple uri parse: return 0 if fail, 1 otherwise*/
int
ocuriparse(const char* uri0, OCURI** ocurip)
{
OCURI* ocuri = NULL;
char* uri;
char** pp;
char* p;
char* p1;
int c;
/* accumulate parse points*/
char* protocol = NULL;
char* params = NULL;
char* host = NULL;
char* port = NULL;
char* constraint = NULL;
char* user = NULL;
char* pwd = NULL;
char* file = NULL;
char* stop;
ocuri = (OCURI*)calloc(1,sizeof(OCURI));
if(ocuri == NULL) return 0;
/* make local copy of uri */
uri = strdup(uri0);
/* remove all whitespace*/
p = uri;
p1 = uri;
while((c=*p1++)) {if(c != ' ' && c != '\t') *p++ = c;}
p = uri;
stop = p + strlen(p);
/* break up the uri string into pieces*/
/* 1. leading bracketed parameters */
if(*p == LBRACKET) {
params = p+1;
/* find end of the clientparams*/
for(;*p;p++) {if(p[0] == RBRACKET && p[1] != LBRACKET) break;}
if(*p == 0) goto fail; /* malformed client params*/
*p = '\0'; /* leave off the trailing rbracket for now */
p++; /* move past the params*/
}
/* verify that the uri starts with an acceptable protocol*/
for(pp=legalprotocols;*pp;pp++) {
if(strncmp(p,*pp,strlen(*pp))==0) break;
}
if(*pp == NULL) goto fail; /* illegal protocol*/
/* save the protocol */
protocol = *pp;
/* 4. skip protocol */
p += strlen(protocol);
/* 5. skip // */
if(*p != '/' && *(p+1) != '/')
goto fail;
p += 2;
/* 6. Mark the end of the host section */
file = strchr(p,'/');
if(file) {
*file++ = '\0'; /* warning: we just overwrote the leading / */
} else
goto fail;
/* 7. extract any user:pwd */
p1 = strchr(p,'@');
if(p1) {/* Assume we have user:pwd@ */
*p1 = '\0';
user = p;
pwd = strchr(p,':');
if(!pwd) goto fail; /* malformed */
*pwd++ = '\0';
p = pwd+strlen(pwd)+1;
}
/* 8. extract host and port */
host = p;
port = strchr(p,':');
if(port) {
*port++ = '\0';
}
/* 9. Look for '?' */
constraint = strchr(file,'?');
if(constraint) {
*constraint++ = '\0';
}
/* assemble the component pieces*/
if(uri0 && strlen(uri0) > 0)
ocuri->uri = strdup(uri0);
if(protocol && strlen(protocol) > 0) {
ocuri->protocol = strdup(protocol);
/* remove trailing ':' */
ocuri->protocol[strlen(protocol)-1] = '\0';
}
if(user && strlen(user) > 0)
ocuri->user = strdup(user);
if(pwd && strlen(pwd) > 0)
ocuri->password = strdup(pwd);
if(host && strlen(host) > 0)
ocuri->host = strdup(host);
if(port && strlen(port) > 0)
ocuri->port = strdup(port);
if(file && strlen(file) > 0) {
/* Add back the leading / */
ocuri->file = malloc(strlen(file)+2);
strcpy(ocuri->file,"/");
strcat(ocuri->file,file);
}
if(constraint && strlen(constraint) > 0)
ocuri->constraint = strdup(constraint);
ocurisetconstraints(ocuri,constraint);
if(params != NULL && strlen(params) > 0) {
ocuri->params = (char*)malloc(1+2+strlen(params));
strcpy(ocuri->params,"[");
strcat(ocuri->params,params);
strcat(ocuri->params,"]");
}
#ifdef OCXDEBUG
{
fprintf(stderr,"ocuri:");
fprintf(stderr," params=|%s|",FIX(ocuri->params));
fprintf(stderr," protocol=|%s|",FIX(ocuri->protocol));
fprintf(stderr," host=|%s|",FIX(ocuri->host));
fprintf(stderr," port=|%s|",FIX(ocuri->port));
fprintf(stderr," file=|%s|",FIX(ocuri->file));
fprintf(stderr," constraint=|%s|",FIX(ocuri->constraint));
fprintf(stderr,"\n");
}
#endif
free(uri);
if(ocurip != NULL) *ocurip = ocuri;
return 1;
fail:
if(ocuri) ocurifree(ocuri);
if(uri != NULL) free(uri);
return 0;
}
void
ocurifree(OCURI* ocuri)
{
if(ocuri == NULL) return;
if(ocuri->uri != NULL) {free(ocuri->uri);}
if(ocuri->protocol != NULL) {free(ocuri->protocol);}
if(ocuri->user != NULL) {free(ocuri->user);}
if(ocuri->password != NULL) {free(ocuri->password);}
if(ocuri->host != NULL) {free(ocuri->host);}
if(ocuri->port != NULL) {free(ocuri->port);}
if(ocuri->file != NULL) {free(ocuri->file);}
if(ocuri->constraint != NULL) {free(ocuri->constraint);}
if(ocuri->projection != NULL) {free(ocuri->projection);}
if(ocuri->selection != NULL) {free(ocuri->selection);}
if(ocuri->params != NULL) {free(ocuri->params);}
if(ocuri->paramlist != NULL) ocparamfree(ocuri->paramlist);
free(ocuri);
}
/* Replace the constraints */
void
ocurisetconstraints(OCURI* duri,const char* constraints)
{
char* proj = NULL;
char* select = NULL;
const char* p;
if(duri->constraint == NULL) free(duri->constraint);
if(duri->projection != NULL) free(duri->projection);
if(duri->selection != NULL) free(duri->selection);
duri->constraint = NULL;
duri->projection = NULL;
duri->selection = NULL;
if(constraints == NULL || strlen(constraints)==0) return;
duri->constraint = strdup(constraints);
if(*duri->constraint == '?')
strcpy(duri->constraint,duri->constraint+1);
p = duri->constraint;
proj = (char*) p;
select = strchr(proj,'&');
if(select != NULL) {
size_t plen = (select - proj);
if(plen == 0) {
proj = NULL;
} else {
proj = (char*)malloc(plen+1);
memcpy((void*)proj,p,plen);
proj[plen] = '\0';
}
select = nulldup(select);
} else {
proj = nulldup(proj);
select = NULL;
}
duri->projection = proj;
duri->selection = select;
}
/* Construct a complete OC URI without the client params
and optionally with the constraints;
caller frees returned string.
Optionally encode the pieces.
*/
char*
ocuribuild(OCURI* duri, const char* prefix, const char* suffix, int flags)
{
size_t len = 0;
char* newuri;
char* tmpfile;
char* tmpsuffix;
char* tmpquery;
int withparams = ((flags&OCURIPARAMS)
&& duri->params != NULL);
int withuserpwd = ((flags&OCURIUSERPWD)
&& duri->user != NULL && duri->password != NULL);
int withconstraints = ((flags&OCURICONSTRAINTS)
&& duri->constraint != NULL);
#ifdef NEWESCAPE
int encode = (flags&OCURIENCODE);
#else
int encode = 0;
#endif
if(prefix != NULL) len += NILLEN(prefix);
if(withparams) {
len += NILLEN("[]");
len += NILLEN(duri->params);
}
len += (NILLEN(duri->protocol)+NILLEN("://"));
if(withuserpwd) {
len += (NILLEN(duri->user)+NILLEN(duri->password)+NILLEN(":@"));
}
len += (NILLEN(duri->host));
if(duri->port != NULL) {
len += (NILLEN(":")+NILLEN(duri->port));
}
tmpfile = duri->file;
if(encode)
tmpfile = ocuriencode(tmpfile,fileallow);
len += (NILLEN(tmpfile));
if(suffix != NULL) {
tmpsuffix = (char*)suffix;
if(encode)
tmpsuffix = ocuriencode(tmpsuffix,fileallow);
len += (NILLEN(tmpsuffix));
}
if(withconstraints) {
tmpquery = duri->constraint;
if(encode)
tmpquery = ocuriencode(tmpquery,queryallow);
len += (NILLEN("?")+NILLEN(tmpquery));
}
len += 1; /* null terminator */
newuri = (char*)malloc(len);
if(!newuri) return NULL;
newuri[0] = '\0';
if(prefix != NULL) strcat(newuri,prefix);
if(withparams) {
strcat(newuri,"[");
strcat(newuri,duri->params);
strcat(newuri,"]");
}
strcat(newuri,duri->protocol);
strcat(newuri,"://");
if(withuserpwd) {
strcat(newuri,duri->user);
strcat(newuri,":");
strcat(newuri,duri->password);
strcat(newuri,"@");
}
if(duri->host != NULL) { /* may be null if using file: protocol */
strcat(newuri,duri->host);
}
if(duri->port != NULL) {
strcat(newuri,":");
strcat(newuri,duri->port);
}
strcat(newuri,tmpfile);
if(suffix != NULL) strcat(newuri,tmpsuffix);
if(withconstraints) {
strcat(newuri,"?");
strcat(newuri,tmpquery);
}
return newuri;
}
/**************************************************/
/* Parameter support */
/*
Client parameters are assumed to be
one or more instances of bracketed pairs:
e.g "[...][...]...".
The bracket content in turn is assumed to be a
comma separated list of <name>=<value> pairs.
e.g. x=y,z=,a=b.
If the same parameter is specifed more than once,
then the first occurrence is used; this is so that
is possible to forcibly override user specified
parameters by prefixing.
IMPORTANT: client parameter string is assumed to
have blanks compress out.
Returns 1 if parse suceeded, 0 otherwise;
*/
int
ocuridecodeparams(OCURI* ocuri)
{
char* cp;
char* cq;
int c;
int i;
int nparams;
char* params0;
char* params;
char* params1;
char** plist;
if(ocuri == NULL) return 0;
if(ocuri->params == NULL) return 1;
params0 = ocuri->params;
/* Pass 1 to replace beginning '[' and ending ']' */
if(params0[0] == '[')
params = strdup(params0+1);
else
params = strdup(params0);
if(params[strlen(params)-1] == ']')
params[strlen(params)-1] = '\0';
/* Pass 2 to replace "][" pairs with ','*/
params1 = strdup(params);
cp=params; cq = params1;
while((c=*cp++)) {
if(c == RBRACKET && *cp == LBRACKET) {cp++; c = ',';}
*cq++ = c;
}
*cq = '\0';
free(params);
params = params1;
/* Pass 3 to break string into pieces and count # of pairs */
nparams=0;
for(cp=params;(c=*cp);cp++) {
if(c == ',') {*cp = '\0'; nparams++;}
}
nparams++; /* for last one */
/* plist is an env style list */
plist = (char**)calloc(1,sizeof(char*)*(2*nparams+1)); /* +1 for null termination */
/* Pass 4 to break up each pass into a (name,value) pair*/
/* and insert into the param list */
/* parameters of the form name name= are converted to name=""*/
cp = params;
for(i=0;i<nparams;i++) {
char* next = cp+strlen(cp)+1; /* save ptr to next pair*/
char* vp;
/*break up the ith param*/
vp = strchr(cp,'=');
if(vp != NULL) {*vp = '\0'; vp++;} else {vp = "";}
plist[2*i] = strdup(cp);
plist[2*i+1] = strdup(vp);
cp = next;
}
plist[2*nparams] = NULL;
free(params);
if(ocuri->paramlist != NULL)
ocparamfree(ocuri->paramlist);
ocuri->paramlist = plist;
return 1;
}
const char*
ocurilookup(OCURI* uri, const char* key)
{
int i;
if(uri == NULL || key == NULL || uri->params == NULL) return NULL;
if(uri->paramlist == NULL) {
i = ocuridecodeparams(uri);
if(!i) return 0;
}
i = ocfind(uri->paramlist,key);
if(i >= 0)
return uri->paramlist[(2*i)+1];
return NULL;
}
int
ocurisetparams(OCURI* uri, const char* newparams)
{
if(uri == NULL) return 0;
if(uri->paramlist != NULL) ocparamfree(uri->paramlist);
uri->paramlist = NULL;
if(uri->params != NULL) free(uri->params);
uri->params = nulldup(newparams);
return 1;
}
/* Internal version of lookup; returns the paired index of the key */
static int
ocfind(char** params, const char* key)
{
int i;
char** p;
for(i=0,p=params;*p;p+=2,i++) {
if(strcmp(key,*p)==0) return i;
}
return -1;
}
static void
ocparamfree(char** params)
{
char** p;
if(params == NULL) return;
for(p=params;*p;p+=2) {
free(*p);
if(p[1] != NULL) free(p[1]);
}
free(params);
}
#ifdef IGNORE
/*
Delete the entry.
return value = 1 => found and deleted;
0 => param not found
*/
int
ocparamdelete(char** params, const char* key)
{
int i;
char** p;
char** q;
if(params == NULL || key == NULL) return 0;
i = ocfind(params,key);
if(i < 0) return 0;
p = params+(2*i);
for(q=p+2;*q;) {
*p++ = *q++;
}
*p = NULL;
return 1;
}
static int
oclength(char** params)
{
int i = 0;
if(params != NULL) {
while(*params) {params+=2; i++;}
}
return i;
}
/*
Insert new client param (name,value);
return value = 1 => not already defined
0 => param already defined (no change)
*/
char**
ocparaminsert(char** params, const char* key, const char* value)
{
int i;
char** newp;
size_t len;
if(params == NULL || key == NULL) return 0;
i = ocfind(params,key);
if(i >= 0) return 0;
/* not found, append */
i = oclength(params);
len = sizeof(char*)*((2*i)+1);
newp = realloc(params,len+2*sizeof(char*));
memcpy(newp,params,len);
newp[2*i] = strdup(key);
newp[2*i+1] = (value==NULL?NULL:strdup(value));
return newp;
}
/*
Replace new client param (name,value);
return value = 1 => replacement performed
0 => key not found (no change)
*/
int
ocparamreplace(char** params, const char* key, const char* value)
{
int i;
if(params == NULL || key == NULL) return 0;
i = ocfind(params,key);
if(i < 0) return 0;
if(params[2*i+1] != NULL) free(params[2*i+1]);
params[2*i+1] = nulldup(value);
return 1;
}
#endif
/* Provide % encoders and decoders */
static char* hexchars = "0123456789abcdef";
static void
toHex(unsigned int b, char hex[2])
{
hex[0] = hexchars[(b >> 4) & 0xff];
hex[1] = hexchars[(b) & 0xff];
}
static unsigned int
fromHex(int c)
{
if(c >= '0' && c <= '9') return (c - '0');
if(c >= 'a' && c <= 'f') return (10 + (c - 'a'));
if(c >= 'A' && c <= 'F') return (10 + (c - 'A'));
return -1;
}
/* Return a string representing encoding of input; caller must free;
watch out: will encode whole string, so watch what you give it.
Allowable argument specifies characters that do not need escaping.
*/
char*
ocuriencode(char* s, char* allowable)
{
size_t slen;
char* encoded;
char* inptr;
char* outptr;
if(s == NULL) return NULL;
slen = strlen(s);
encoded = (char*)malloc((3*slen) + 1); /* max possible size */
for(inptr=s,outptr=encoded;*inptr;) {
int c = *inptr++;
if(c == ' ') {
*outptr++ = '+';
} else {
// search allowable
int c2;
char* a = allowable;
while((c2=*a++)) {
if(c == c2) break;
}
if(c2) {*outptr++ = c;}
else {
char hex[2];
toHex(c,hex);
*outptr++ = '%';
*outptr++ = hex[0];
*outptr++ = hex[1];
}
}
}
*outptr = '\0';
return encoded;
}
/* Return a string representing decoding of input; caller must free;*/
char*
ocuridecode(char* s)
{
size_t slen;
char* decoded;
char* outptr;
char* inptr;
unsigned int c;
if (s == NULL) return NULL;
slen = strlen(s);
decoded = (char*)malloc(slen+1); // Should be max we need
outptr = decoded;
inptr = s;
while((c = *inptr++)) {
if(c == '+')
*outptr++ = ' ';
else if(c == '%') {
/* try to pull two more characters */
int x0, x1;
x0 = inptr[0];
if(x0 != '\0') {
x1 = inptr[1];
if(x0 != '\0') {
c = (fromHex(x0) << 4) | (fromHex(x1));
inptr += 2;
}
}
}
*outptr++ = c;
}
*outptr = '\0';
return decoded;
}