Bar step-internal params from influencing pipeline driver init (#729)

In cases such as:

proj=pipeline step proj=utm zone=32 ellps=GRS80 ...

The pj_init code would pick up the ellps information (and other material such as false eastings and northings) from the utm step and place it into the PJ object of the pipeline driver.

This is not the intention, and is eliminated in this PR by terminating parameter searching (done by pj_param) once a step parameter is reached.

1 files changed, 68 insertions, 56 deletions

diff --git a/src/pj_param.c b/src/pj_param.c
index 5024346d..72175ed9 100644
--- a/src/pj_param.c
+++ b/src/pj_param.c
@@ -56,6 +56,11 @@ paralist *pj_param_exists (paralist *list, const char *parameter) {
     Determine whether a given parameter exists in a paralist. If it does, return
     a pointer to the corresponding list element - otherwise return 0.
 
+    In support of the pipeline syntax, the search is terminated once a "+step" list
+    element is reached, in which case a 0 is returned, unless the parameter
+    searched for is actually "step", in which case a pointer to the "step" list
+    element is returned.
+
     This function is equivalent to the pj_param (...) call with the "opt" argument
     set to the parameter name preceeeded by a 't'. But by using this one, one avoids
     writing the code allocating memory for a new copy of parameter name, and prepending
@@ -69,9 +74,12 @@ paralist *pj_param_exists (paralist *list, const char *parameter) {
     if (list==0)
         return 0;
 
-    for (next = list; next; next = next->next)
+    for (next = list; next; next = next->next) {
         if (0==strncmp (parameter, next->param, len) && (next->param[len]=='=' || next->param[len]==0))
             return next;
+        if (0==strcmp (parameter, "step"))
+            return 0;
+    }
 
     return 0;
 }
@@ -92,78 +100,82 @@ paralist *pj_param_exists (paralist *list, const char *parameter) {
 /*       `s' - string returned in PROJVALUE.s                           */
 /*       `b' - test for t/T/f/F, return in PROJVALUE.i                  */
 /*                                                                      */
+/*      Search is terminated when "step" is found, in which case        */
+/*      0 is returned, unless "step" was the target searched for.       */
+/*                                                                      */
 /************************************************************************/
 
-    PROJVALUE /* test for presence or get parameter value */
-pj_param(projCtx ctx, paralist *pl, const char *opt) {
+PROJVALUE pj_param (projCtx ctx, paralist *pl, const char *opt) {
 
     int type;
     unsigned l;
-    PROJVALUE value;
+    PROJVALUE value = {0};
 
-    if( ctx == NULL )
+    if ( ctx == NULL )
         ctx = pj_get_default_ctx();
 
     type = *opt++;
-    /* simple linear lookup */
-    l = (int)strlen(opt);
-    while (pl && !(!strncmp(pl->param, opt, l) &&
-      (!pl->param[l] || pl->param[l] == '=')))
-        pl = pl->next;
-    if (type == 't')
+
+    if (0==strchr ("tbirds", type)) {
+        fprintf(stderr, "invalid request to pj_param, fatal\n");
+        exit(1);
+    }
+
+    pl = pj_param_exists (pl, opt);
+    if (type == 't') {
         value.i = pl != 0;
-    else if (pl) {
-        pl->used |= 1;
-        opt = pl->param + l;
-        if (*opt == '=')
-            ++opt;
-        switch (type) {
-        case 'i':	/* integer input */
-            value.i = atoi(opt);
-            break;
-        case 'd':	/* simple real input */
-            value.f = pj_atof(opt);
-            break;
-        case 'r':	/* degrees input */
-            value.f = dmstor_ctx(ctx, opt, 0);
-            break;
-        case 's':	/* char string */
-                        value.s = (char *) opt;
-            break;
-        case 'b':	/* boolean */
-            switch (*opt) {
-            case 'F': case 'f':
-                value.i = 0;
-                break;
-            case '\0': case 'T': case 't':
-                value.i = 1;
-                break;
-            default:
-                pj_ctx_set_errno(ctx, -8);
-                value.i = 0;
-                break;
-            }
-            break;
-        default:
-bum_type:	/* note: this is an error in parameter, not a user error */
-            fprintf(stderr, "invalid request to pj_param, fatal\n");
-            exit(1);
-        }
-    } else /* not given */
+        return value;
+    }
+
+    /* Not found */
+    if (0==pl) {
         switch (type) {
-        case 'b':
-        case 'i':
+        case 'b': case 'i':
             value.i = 0;
-            break;
-        case 'd':
-        case 'r':
+            return value;
+        case 'd': case 'r':
             value.f = 0.;
-            break;
+            return value;
         case 's':
             value.s = 0;
+            return value;
+        }
+    }
+
+    /* Found parameter - now find its value */
+    pl->used |= 1;
+    l = (int) strlen(opt);
+    opt = pl->param + l;
+    if (*opt == '=')
+        ++opt;
+
+    switch (type) {
+    case 'i':    /* integer input */
+        value.i = atoi(opt);
+        break;
+    case 'd':    /* simple real input */
+        value.f = pj_atof(opt);
+        break;
+    case 'r':    /* degrees input */
+        value.f = dmstor_ctx(ctx, opt, 0);
+        break;
+    case 's':    /* char string */
+        value.s = (char *) opt;
+        break;
+    case 'b':    /* boolean */
+        switch (*opt) {
+        case 'F': case 'f':
+            value.i = 0;
+            break;
+        case '\0': case 'T': case 't':
+            value.i = 1;
             break;
         default:
-            goto bum_type;
+            pj_ctx_set_errno (ctx, PJD_ERR_INVALID_BOOLEAN_PARAM);
+            value.i = 0;
+            break;
         }
+        break;
+    }
     return value;
 }