I'm working on an embedded platform and I am trying to access a MariaDB through unixODBC. Trying to test the connection with isql I get the response:
isql -v mydsn myuser mypw
[01000][unixODBC][Driver Manager]Can't open lib '/usr/lib/libmaodbc.so' : file not found
The file /usr/lib/libmaodbc.so exists:
ls -la /usr/lib/libmaodbc.so
-r-xr-xr-x 1 root root 403952 Sep 1 00:00 /usr/lib/libmaodbc.so
So I figured a dependency must be missing.
readelf -d /usr/lib/libmaodbc.so
Dynamic section at offset 0x4fb54 contains 30 entries:
Tag Type Name/Value
0x00000001 (NEEDED) Shared library: [libodbcinst.so.2]
0x00000001 (NEEDED) Shared library: [libm.so.6]
0x00000001 (NEEDED) Shared library: [libc.so.6]
0x00000001 (NEEDED) Shared library: [ld-linux-armhf.so.3]
0x0000000e (SONAME) Library soname: [libmaodbc.so]
[...]
I repeated the check - all four dependencies exist.
Next I wrote a test program, which tries to load the shared objects:
#include <iostream>
#include <dlfcn.h>
void tryLoadSo(const std::string& path) {
void* so = dlopen(path.c_str(), RTLD_NOW);
if(so) {
std::cout << "Loaded " << path << "!" << std::endl;
dlclose(so);
} else {
std::cout << "Failed to load " << path << "!" << std::endl;
}
}
int main() {
tryLoadSo("/usr/lib/libmaodbc.so");
tryLoadSo("/usr/lib/libodbcinst.so.2");
tryLoadSo("/usr/lib/libm.so.6");
tryLoadSo("/usr/lib/libc.so.6");
tryLoadSo("/usr/lib/ld-linux-armhf.so.3");
}
Output:
Failed to load /usr/lib/libmaodbc.so!
Loaded /usr/lib/libodbcinst.so.2!
Loaded /usr/lib/libm.so.6!
Loaded /usr/lib/libc.so.6!
Loaded /usr/lib/ld-linux-armhf.so.3!
Thus all the dependencies can be loaded, but libmaodbc cannot.
Is the shared object not configured for the correct plattform? Yes, it is. I compared it to libodbcinst.so.2 to make sure:
readelf -h /usr/lib/libmaodbc.so
ELF Header:
Magic: 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: ARM
Version: 0x1
Entry point address: 0x9a58
Start of program headers: 52 (bytes into file)
Start of section headers: 402952 (bytes into file)
Flags: 0x5000400, Version5 EABI, hard-float ABI
Size of this header: 52 (bytes)
Size of program headers: 32 (bytes)
Number of program headers: 7
Size of section headers: 40 (bytes)
Number of section headers: 25
Section header string table index: 24
readelf -h /usr/lib/libodbcinst.so.2
ELF Header:
Magic: 7f 45 4c 46 01 01 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, little endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: ARM
Version: 0x1
Entry point address: 0x1e60
Start of program headers: 52 (bytes into file)
Start of section headers: 53528 (bytes into file)
Flags: 0x5000400, Version5 EABI, hard-float ABI
Size of this header: 52 (bytes)
Size of program headers: 32 (bytes)
Number of program headers: 6
Size of section headers: 40 (bytes)
Number of section headers: 24
Section header string table index: 23
What could be going wrong? Why won't libmaodbc.so load?
