obs_api revision and improvements: new namespace etc. (#530)

* obs_api revision and improvements: new namespace etc.

* Minor corrections: use unused functions, add missing prototype, added fwd/invcoord to PJ

* Minor correction: MSVC barfs on va_arg type specification. Trying once more with added parens

* Reverting paren correction, which appears to be a non-solution

* Significant improvements to the OBS_API, plus a number of corrections, mostly in test code, to reflect API changes

* Added two missing prototypes

* Adding the proj_transform function and some related checks

* Improvements to proj_transform etc. based on suggestions from Even Rouault

* Reducing the libc include footprint of proj.h - again based on suggestions from Even Rouault

* A few minor corrections

* Eliminate a MSVC warning about non-initialized usage. Not an actual issue, as another check has locked the path, but at least this should calm down MSVC

* Improved support for the errno reset/restore paradigm

* Introduced the internal header proj_internal.h; Moved most non-API stuff from pj_obs_api.c to pj_internal.c

* Adding proj_internal.h to HEADERS_LIBPROJ to solve build problems

* Correcting a few pj...proj blunders in PJ_pipeline.c

* Correcting a few additional blunders in PJ_pipeline.c

* Changed angle-brackets to quotation marks in includes of proj_internal.h

* Some minor build system repairs

* Some PJ_CONTEXT usage simplifications following suggestions by Kristian Evers @kbevers

* Added version numbering to proj.h - Fixes #529

* remove proj_errno_restore macro, provide function implementation

* Add proj_get_definition. Fixes #538

* Added library specific deallocator proj_buffer_free, eliminating a potential cross heap issues on Windows. Thx to Even Rouault for spotting this

* Got rid of a meaningless cast in proj_buffer_free

* Added some missing functions to proj.def (again spotted by @rouault); removed some not-yet-implemented material from proj.h

* Renamed proj_get_definition/proj_buffer_free to proj_definition_create/proj_definition_destroy, for symmetry and clarity

* Renaming the definition handlers to proj_definition_retrieve / proj_free

* Renaming proj_free to proj_release

1 files changed, 236 insertions, 0 deletions

diff --git a/src/pj_internal.c b/src/pj_internal.c
new file mode 100644
index 00000000..f3ca3566
--- /dev/null
+++ b/src/pj_internal.c
@@ -0,0 +1,236 @@
+/******************************************************************************
+ * Project:  PROJ.4
+ * Purpose:  This is primarily material originating from pj_obs_api.c,
+ *           that does not fit into the API category. Hence this pile of
+ *           tubings and fittings for PROJ.4 internal plumbing.
+ *
+ * Author:   Thomas Knudsen,  thokn@sdfe.dk,  2017-07-05
+ *
+ ******************************************************************************
+ * Copyright (c) 2016, 2017, Thomas Knudsen/SDFE
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *****************************************************************************/
+#define PJ_INTERNAL_C
+#include "proj_internal.h"
+#include <projects.h>
+#include <geodesic.h>
+
+#include <stddef.h>
+#include <stdarg.h>
+#include <errno.h>
+
+
+
+
+/* Used for zero-initializing new objects */
+const PJ_COORD proj_coord_null = {{0, 0, 0, 0}};
+const PJ_OBS   proj_obs_null = {
+    {{0, 0, 0, 0}},
+    {{0, 0, 0}},
+    0, 0
+};
+
+
+/* Work around non-constness of MSVC HUGE_VAL by providing functions rather than constants */
+PJ_COORD proj_coord_error (void) {
+    PJ_COORD c;
+    c.v[0] = c.v[1] = c.v[2] = c.v[3] = HUGE_VAL;
+    return c;
+}
+
+PJ_OBS proj_obs_error (void) {
+    PJ_OBS obs;
+    obs.coo = proj_coord_error ();
+    obs.anc.v[0] = obs.anc.v[1] = obs.anc.v[2] = HUGE_VAL;
+    obs.id = obs.flags = 0;
+    return obs;
+}
+
+
+
+PJ_OBS pj_fwdobs (PJ_OBS obs, PJ *P) {
+    if (0!=P->fwdobs) {
+        obs  =  P->fwdobs (obs, P);
+        return obs;
+    }
+    if (0!=P->fwd3d) {
+        obs.coo.xyz  =  pj_fwd3d (obs.coo.lpz, P);
+        return obs;
+    }
+    if (0!=P->fwd) {
+        obs.coo.xy  =  pj_fwd (obs.coo.lp, P);
+        return obs;
+    }
+    proj_errno_set (P, EINVAL);
+    return proj_obs_error ();
+}
+
+
+PJ_OBS pj_invobs (PJ_OBS obs, PJ *P) {
+    if (0!=P->invobs) {
+        obs  =  P->invobs (obs, P);
+        return obs;
+    }
+    if (0!=P->inv3d) {
+        obs.coo.lpz  =  pj_inv3d (obs.coo.xyz, P);
+        return obs;
+    }
+    if (0!=P->inv) {
+        obs.coo.lp  =  pj_inv (obs.coo.xy, P);
+        return obs;
+    }
+    proj_errno_set (P, EINVAL);
+    return proj_obs_error ();
+}
+
+
+
+PJ_COORD pj_fwdcoord (PJ_COORD coo, PJ *P) {
+    if (0!=P->fwdcoord)
+        return P->fwdcoord (coo, P);
+    if (0!=P->fwdobs) {
+        PJ_OBS obs = proj_obs_null;
+        obs.coo = coo;
+        obs  =  P->fwdobs (obs, P);
+        return obs.coo;
+    }
+    if (0!=P->fwd3d) {
+        coo.xyz  =  pj_fwd3d (coo.lpz, P);
+        return coo;
+    }
+    if (0!=P->fwd) {
+        coo.xy  =  pj_fwd (coo.lp, P);
+        return coo;
+    }
+    proj_errno_set (P, EINVAL);
+    return proj_coord_error ();
+}
+
+
+PJ_COORD pj_invcoord (PJ_COORD coo, PJ *P) {
+    if (0!=P->invcoord)
+        return P->invcoord (coo, P);
+    if (0!=P->invobs) {
+        PJ_OBS obs = proj_obs_null;
+        obs.coo = coo;
+        obs  =  P->invobs (obs, P);
+        return obs.coo;
+    }
+    if (0!=P->inv3d) {
+        coo.lpz  =  pj_inv3d (coo.xyz, P);
+        return coo;
+    }
+    if (0!=P->inv) {
+        coo.lp  =  pj_inv (coo.xy, P);
+        return coo;
+    }
+    proj_errno_set (P, EINVAL);
+    return proj_coord_error ();
+}
+
+
+
+
+
+/* Move P to a new context - or to the default context if 0 is specified */
+void proj_context_set (PJ *P, PJ_CONTEXT *ctx) {
+    if (0==ctx)
+        ctx = pj_get_default_ctx ();
+    pj_set_ctx (P, ctx);
+    return;
+}
+
+void proj_context_inherit (PJ *parent, PJ *child) {
+    if (0==parent)
+        pj_set_ctx (child, pj_get_default_ctx());
+    else
+        pj_set_ctx (child, pj_get_ctx(parent));
+    return;
+}
+
+
+
+
+
+/* stuff below is *not* considered API, and will be moved to an "internal plumbing toolset" */
+
+
+
+void proj_context_errno_set (PJ_CONTEXT *ctx, int err) {
+    if (0==ctx)
+        ctx = pj_get_default_ctx();
+    pj_ctx_set_errno (ctx, err);
+    return;
+}
+
+
+
+/* Set logging level 0-3. Higher number means more debug info. 0 turns it off */
+enum proj_log_level proj_log_level (PJ_CONTEXT *ctx, enum proj_log_level log_level) {
+    enum proj_log_level previous;
+    if (0==ctx)
+        ctx = pj_get_default_ctx();
+    if (0==ctx)
+        return PJ_LOG_TELL;
+    previous = ctx->debug_level;
+    if (PJ_LOG_TELL==log_level)
+        return previous;
+    ctx->debug_level = log_level;
+    return previous;
+}
+
+
+
+/*  logging  */
+
+/* pj_vlog resides in pj_log.c and relates to pj_log as vsprintf relates to sprintf */
+void pj_vlog( projCtx ctx, int level, const char *fmt, va_list args );
+
+void proj_log_error (PJ *P, const char *fmt, ...) {
+    va_list args;
+    va_start( args, fmt );
+    pj_vlog (pj_get_ctx (P), PJ_LOG_ERROR , fmt, args);
+    va_end( args );
+}
+
+void proj_log_debug (PJ *P, const char *fmt, ...) {
+    va_list args;
+    va_start( args, fmt );
+    pj_vlog (pj_get_ctx (P), PJ_LOG_DEBUG_MAJOR , fmt, args);
+    va_end( args );
+}
+
+void proj_log_trace (PJ *P, const char *fmt, ...) {
+    va_list args;
+    va_start( args, fmt );
+    pj_vlog (pj_get_ctx (P), PJ_LOG_DEBUG_MINOR , fmt, args);
+    va_end( args );
+}
+
+/* Put a new logging function into P's context. The opaque object app_data is passed as first arg at each call to the logger */
+void proj_log_func (PJ_CONTEXT *ctx, void *app_data, PJ_LOG_FUNCTION log) {
+    if (0==ctx)
+        pj_get_default_ctx ();
+    if (0==ctx)
+        return;
+    ctx->app_data = app_data;
+    if (0!=log)
+        ctx->logger = log;
+}