Actual source code: memc.c
petsc-3.8.4 2018-03-24
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.
7: */
8: #include <petscsys.h>
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
15: /*@
16: PetscMemcmp - Compares two byte streams in memory.
18: Not Collective
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)
26: Output Parameters:
27: . e - PETSC_TRUE if equal else PETSC_FALSE.
29: Level: intermediate
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;
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: return(0);
45: }
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.
52: Not Collective
54: Input Parameters:
55: + b - pointer to initial memory space
56: - n - length (in bytes) of space to copy
58: Output Parameter:
59: . a - pointer to copy space
61: Level: intermediate
63: Note:
64: This routine is analogous to memmove().
66: Since b can overlap with a, b cannot be declared as const
68: Concepts: memory^copying with overlap
69: Concepts: copying^memory with overlap
71: .seealso: PetscMemcpy()
72: @*/
73: PetscErrorCode PetscMemmove(void *a,void *b,size_t n)
74: {
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: return(0);
96: }