1 2 /* 3 We define the memory operations here. The reason we just do not use 4 the standard memory routines in the PETSc code is that on some machines 5 they are broken. 6 7 */ 8 #include <petscsys.h> /*I "petscsys.h" I*/ 9 #include <petscbt.h> 10 #include <../src/sys/utils/ftn-kernels/fcopy.h> 11 #if defined(PETSC_HAVE_STRING_H) 12 #include <string.h> 13 #endif 14 15 /*@ 16 PetscMemcmp - Compares two byte streams in memory. 17 18 Not Collective 19 20 Input Parameters: 21 + str1 - Pointer to the first byte stream 22 . str2 - Pointer to the second byte stream 23 - len - The length of the byte stream 24 (both str1 and str2 are assumed to be of length len) 25 26 Output Parameters: 27 . e - PETSC_TRUE if equal else PETSC_FALSE. 28 29 Level: intermediate 30 31 Note: 32 This routine is anologous to memcmp() 33 @*/ 34 PetscErrorCode PetscMemcmp(const void *str1,const void *str2,size_t len,PetscBool *e) 35 { 36 int r; 37 38 PetscFunctionBegin; 39 if (len > 0 && !str1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Trying to compare at a null pointer"); 40 if (len > 0 && !str2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Trying to compare at a null pointer"); 41 r = memcmp((char*)str1,(char*)str2,len); 42 if (!r) *e = PETSC_TRUE; 43 else *e = PETSC_FALSE; 44 PetscFunctionReturn(0); 45 } 46 47 /*@ 48 PetscMemmove - Copies n bytes, beginning at location b, to the space 49 beginning at location a. Copying between regions that overlap will 50 take place correctly. 51 52 Not Collective 53 54 Input Parameters: 55 + b - pointer to initial memory space 56 - n - length (in bytes) of space to copy 57 58 Output Parameter: 59 . a - pointer to copy space 60 61 Level: intermediate 62 63 Note: 64 This routine is analogous to memmove(). 65 66 Since b can overlap with a, b cannot be declared as const 67 68 Concepts: memory^copying with overlap 69 Concepts: copying^memory with overlap 70 71 .seealso: PetscMemcpy() 72 @*/ 73 PetscErrorCode PetscMemmove(void *a,void *b,size_t n) 74 { 75 PetscFunctionBegin; 76 if (n > 0 && !a) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Trying to copy to null pointer"); 77 if (n > 0 && !b) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Trying to copy from a null pointer"); 78 #if !defined(PETSC_HAVE_MEMMOVE) 79 if (a < b) { 80 if (a <= b - n) memcpy(a,b,n); 81 else { 82 memcpy(a,b,(int)(b - a)); 83 PetscMemmove(b,b + (int)(b - a),n - (int)(b - a)); 84 } 85 } else { 86 if (b <= a - n) memcpy(a,b,n); 87 else { 88 memcpy(b + n,b + (n - (int)(a - b)),(int)(a - b)); 89 PetscMemmove(a,b,n - (int)(a - b)); 90 } 91 } 92 #else 93 memmove((char*)(a),(char*)(b),n); 94 #endif 95 PetscFunctionReturn(0); 96 } 97 98 99 100 101