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, 115 insertions, 0 deletions

diff --git a/src/proj_internal.h b/src/proj_internal.h
new file mode 100644
index 00000000..da457077
--- /dev/null
+++ b/src/proj_internal.h
@@ -0,0 +1,115 @@
+/******************************************************************************
+ * Project:  PROJ.4
+ * Purpose:  Internal plumbing for the PROJ.4 library.
+ *
+ * Author:   Thomas Knudsen, <thokn@sdfe.dk>
+ *
+ ******************************************************************************
+ * 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 COORD 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.
+ *****************************************************************************/
+
+#ifdef _MSC_VER
+#ifndef _USE_MATH_DEFINES
+#define _USE_MATH_DEFINES
+#endif
+#endif
+#include <math.h>   /* For M_PI */
+
+#include <proj.h>
+
+#ifdef PROJECTS_H
+#error proj_internal.h must be included before projects.h
+#endif
+#ifdef PROJ_API_H
+#error proj_internal.h must be included before proj_api.h
+#endif
+
+#ifndef PROJ_INTERNAL_H
+#define PROJ_INTERNAL_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+
+#ifndef PJ_TODEG
+#define PJ_TODEG(rad)  ((rad)*180.0/M_PI)
+#endif
+#ifndef PJ_TORAD
+#define PJ_TORAD(deg)  ((deg)*M_PI/180.0)
+#endif
+
+
+
+PJ_COORD proj_coord_error (void);
+PJ_OBS   proj_obs_error (void);
+#ifndef PJ_INTERNAL_C
+extern const PJ_COORD proj_coord_null;
+extern const PJ_OBS   proj_obs_null;
+#endif
+/* Part of MSVC workaround: Make proj_*_null look function-like for symmetry with proj_*_error */
+#define proj_coord_null(x) proj_coord_null
+#define proj_obs_null(x) proj_obs_null
+
+
+void proj_context_errno_set (PJ_CONTEXT *ctx, int err);
+void proj_context_set (PJ *P, PJ_CONTEXT *ctx);
+void proj_context_inherit (PJ *parent, PJ *child);
+
+
+PJ_OBS pj_fwdobs (PJ_OBS obs, PJ *P);
+PJ_OBS pj_invobs (PJ_OBS obs, PJ *P);
+PJ_COORD pj_fwdcoord (PJ_COORD coo, PJ *P);
+PJ_COORD pj_invcoord (PJ_COORD coo, PJ *P);
+
+
+
+/* High level functionality for handling thread contexts */
+enum proj_log_level {
+    PJ_LOG_NONE  = 0,
+    PJ_LOG_ERROR = 1,
+    PJ_LOG_DEBUG = 2,
+    PJ_LOG_TRACE = 3,
+    PJ_LOG_TELL  = 4,
+    PJ_LOG_DEBUG_MAJOR = 2, /* for proj_api.h compatibility */
+    PJ_LOG_DEBUG_MINOR = 3  /* for proj_api.h compatibility */
+};
+
+/* 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);
+typedef void (*PJ_LOG_FUNCTION)(void *, int, const char *);
+
+void proj_log_error (PJ *P, const char *fmt, ...);
+void proj_log_debug (PJ *P, const char *fmt, ...);
+void proj_log_trace (PJ *P, const char *fmt, ...);
+/*void proj_log_func (PJ *P, void *app_data, void (*log)(void *, int, const char *));*/
+void proj_log_func (PJ_CONTEXT *ctx, void *app_data, PJ_LOG_FUNCTION log);
+
+
+/* Lowest level: Minimum support for fileapi */
+void proj_fileapi_set (PJ *P, void *fileapi);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ndef PROJ_INTERNAL_H */