Fortran Support in ZOO Kernel
This page will contain full information about the Fortran support in the ZOO Kernel.
Fortran code snipest
Let us create a small example of a Fortran function which simply multiply by two the value passed as argument.
C ex4.for
C ARRAYS X, Y and Z are respectively :
C main_conf, inputs and outputs
FUNCTION HELLOWORLD(X, Y, Z, X0) RESULT (R)
INTEGER(4) :: R
CHARACTER*1024 X(10,10)
CHARACTER*1024 Y(10,10)
CHARACTER*1024 Z(10,10)
CHARACTER*100 X0
CHARACTER*1024 TMP
C CHARACTER*(*) X(1:10,1:10), Y(1:10,1:10), Z(1:10,1:10)
PRINT *,'FROM FORTRAN : '//X0//'\n'
C PRINT *,'FROM FORTRAN Y(1,1) : ('//Y(1,1)//')\n'
C DO i = 2,10
C DO j = 2, 10
C PRINT *,'FROM FORTRAN Y(',j,',',i,') = ['//Y(j,i)//']\n'
C END DO
C END DO
PRINT *,'FROM FORTRAN Y(1,1) = ('//Y(1,1)//')\n'
PRINT *,'FROM FORTRAN Y(2,1) = ('//Y(2,1)//')\n'
PRINT *,'FROM FORTRAN Y(3,1) = ('//Y(3,1)//')\n'
PRINT *,'FROM FORTRAN Y(4,1) = ('//Y(4,1)//')\n'
Z(2,1) = TRIM('name')//CHAR(0)
Z(5,1) = 'result'//CHAR(0)
Z(8,1) = 'value'//CHAR(0)
Z(1,2) = 'Hello from the Fortran world !'//CHAR(0)
Z(4,2) = 'datattype'//CHAR(0)
Z(7,2) = 'string'//CHAR(0)
Z(3,1) = 'name'//CHAR(0)
Z(6,1) = 'result'//CHAR(0)
Z(9,1) = 'value'//CHAR(0)
Z(2,2) = 'Hello from the Fortran world !'//CHAR(0)
Z(5,2) = 'datatype'//CHAR(0)
Z(8,2) = 'string'//CHAR(0)
C DO i = 1,10
C DO j = 1, 10
C PRINT *,'FROM FORTRAN Z(',j,',',i,') = ['//Z(j,i)//']\n'
C END DO
C END DO
C PRINT *,Z(1,2)
C PRINT *,TMP
R = 3
END
To create a shared library of this code snipest, use the following command :
gfortran -fno-f2c -shared -s -o ex4.so ex4.for
Then the loading process isthe same as before, using the dlload, dlsym then use the funcion.
The snipest C++ code bellow will load, extract the function from the fortran shared library then run the function and finally close the shared library.
// ex4fortranloader.c #include <iostream> #include <dlfcn.h> void inplace_trim(char* s) { int start, end = strlen(s); for (start = 0; s[start] && isspace(s[start]); ++start) {} if (s[start]) { while (end > 0 && isspace(s[end-1])) --end; } memmove(s, &s[start], end - start); s[end - start] = '\0'; } int main() { void *hDll = dlopen("./ex3.so", RTLD_NOW); typedef int (* LPFNDLLFUNC) (char***,char***,char***,char*); LPFNDLLFUNC lpFunc = NULL; lpFunc = (LPFNDLLFUNC)dlsym(hDll, "helloworld_"); int i, numPts = 10; /** * Creating the string matrix contigous */ char main_conf[10][10][1024]; char inputs[10][10][1024]; char outputs[10][10][1024]; printf("first allocation has been made\n"); for(int i=0;i<10;i++){ for(int j=0;j<10;j++){ memset(main_conf[i][j],0,1024); memset(inputs[i][j],0,1024); memset(outputs[i][j],0,1024); } } sprintf(inputs[0][0],"name"); inputs[0][0][4]=0; printf("inputs[0][0] = %s\n",inputs[0][0]); sprintf(inputs[0][1],"S"); inputs[0][1][1]=0; printf("inputs[0][1] = %s\n",inputs[0][1]); sprintf(inputs[0][2],"value"); inputs[0][2][5]=0; printf("inputs[0][2] = %s\n",inputs[0][2]); sprintf(inputs[0][3]," Your Name Here "); inputs[0][3][16]=0; printf("inputs[0][3] = %s\n",inputs[0][3]); printf("Allocation made of inputs values\n"); char *tmp=(char*)malloc(100*sizeof(char)); sprintf(tmp,"My Test String"); int res=lpFunc(main_conf,inputs,outputs,tmp); printf("function ran successfully and retruned : %d\n",res); fflush(stderr); fflush(stdout); i=0; for(int j=0;j<10;j++){ inplace_trim(inputs[i][j]); printf("Y(%d,%d)='%s' ",j+1,i+1,inputs[i][j]); } printf("\n****************\n"); for(int j=0;j<10;j++){ inplace_trim(outputs[i][j]); printf("Z(%d,%d)='%s' ",j+1,i+1,outputs[i][j]); } printf("\n****************\n"); dlclose(hDll); return 0; }
Compile this code using the following command :
g++ -o ex1fortranloader ex1fortranloader.cpp -ldl
Now, to process the function you'll only have to run the following command :
./ex1fortranloader
Which should output :
first allocation has been made inputs[0][0] = name inputs[0][1] = S inputs[0][2] = value inputs[0][3] = Your Name Here Allocation made of inputs values FROM FORTRAN : Your Name Here FROM FORTRAN Y(2,1) = ( name) FROM FORTRAN Y(5,1) = ( S) FROM FORTRAN Y(8,1) = ( value) FROM FORTRAN Y(1,2) = ( Your Name Here) function ran successfully and retruned : 3 Y(1,1)='name' Y(2,1)='result' Y(3,1)='value' Y(4,1)='Hello from the Fortran world !' Y(5,1)='datatype' Y(6,1)='string' Y(7,1)='' Y(8,1)='' Y(9,1)='' Y(10,1)='' **************** Z(1,1)='' Z(2,1)='' Z(3,1)='' Z(4,1)='' Z(5,1)='' Z(6,1)='' Z(7,1)='' Z(8,1)='' Z(9,1)='' Z(10,1)='' ****************
Conclusion
So we can say that loading a C SSO (Service Shared Object) or a Fortran one work in the same way.
The goal is now to be able to pass maps* datastructure to the fortran function then let user easily get/set its data using this datastructure. Maybe a simple multidimentional array of CHARACTER* can be used. This way maps will be translated into CHARACTERS*1024 A(10,10) before being passed to the Fortran function. So this way we would get a 10*10 matrix of 1024 bytes length string.
Hopefully the code provided here display well the result value in the right array (matrix!? :) ).
