eina: Rename EAPI macro to EINA_API in Eina library

Summary:
Patch from a series of patches to rename EAPI symbols to specific
library DSOs.

EAPI was designed to be able to pass
`__attribute__ ((visibility ("default")))` for symbols with
GCC, which would mean that even if -fvisibility=hidden was used
when compiling the library, the needed symbols would get exported.

MSVC __almost__ works like GCC (or mingw) in which you can
declare everything as export and it will just work (slower, but
it will work). But there's a caveat: global variables will not
work the same way for MSVC, but works for mingw and GCC.

For global variables (as opposed to functions), MSVC requires
correct DSO visibility for MSVC: instead of declaring a symbol as
export for everything, you need to declare it as import when
importing from another DSO and export when defining it locally.

With current EAPI definitions, we get the following example
working in mingw and MSVC (observe it doesn't define any global
variables as exported symbols).

Example 1:
dll1:
```
EAPI void foo(void);

EAPI void bar()
{
  foo();
}
```
dll2:
```
EAPI void foo()
{
  printf ("foo\n");
}
```

This works fine with API defined as __declspec(dllexport) in both
cases and for gcc defining as
`__atttribute__((visibility("default")))`

However, the following:
Example 2:

dll1:

```
EAPI extern int foo;
EAPI void foobar(void);

EAPI void bar()
{
  foo = 5;
  foobar();
}
```

dll2:

```
EAPI int foo = 0;
EAPI void foobar()
{
  printf ("foo %d\n", foo);
}
```

This will work on mingw but will not work for MSVC. And that's why
EAPI is the only solution that worked for MSVC.

Co-authored-by: João Paulo Taylor Ienczak Zanette <jpaulotiz@gmail.com>
Co-authored-by: Ricardo Campos <ricardo.campos@expertise.dev>
Co-authored-by: Lucas Cavalcante de Sousa <lucks.sousa@gmail.com>

Reviewers: jptiz, lucas, woohyun, vtorri, raster

Reviewed By: jptiz, lucas, vtorri

Subscribers: ProhtMeyhet, cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D12188

2 files changed, 1 insertions, 4 deletions

diff --git a/src/tests/eina/eina_test_abi.c b/src/tests/eina/eina_test_abi.c
index 6c49544fdd..e1e1423d03 100644
--- a/src/tests/eina/eina_test_abi.c
+++ b/src/tests/eina/eina_test_abi.c
@@ -43,9 +43,6 @@ typedef uint32_t Eina_Unicode;
 #include "eina_main.h"
 #include "eina_safety_checks.h"
 
-EAPI Eina_Unicode eina_unicode_utf8_get_next(const char *buf, int *iindex);
-EAPI unsigned int eina_mempool_alignof(unsigned int size);
-
 EFL_START_TEST(eina_unicode_utf8)
 {
    int ind;
diff --git a/src/tests/eina/eina_test_module_dummy.c b/src/tests/eina/eina_test_module_dummy.c
index bb9916db43..aa136ebe8f 100644
--- a/src/tests/eina/eina_test_module_dummy.c
+++ b/src/tests/eina/eina_test_module_dummy.c
@@ -16,7 +16,7 @@ void dummy_module_shutdown(void)
 
 }
 
-EAPI int dummy_symbol = 0xbad;
+EINA_API int dummy_symbol = 0xbad;
 
 EINA_MODULE_INIT(dummy_module_init);
 EINA_MODULE_SHUTDOWN(dummy_module_shutdown);