strtotm.c 1.9 KB

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  1. #include <u.h>
  2. #include <libc.h>
  3. #include <ctype.h>
  4. static char*
  5. skiptext(char *q)
  6. {
  7. while(*q!='\0' && *q!=' ' && *q!='\t' && *q!='\r' && *q!='\n')
  8. q++;
  9. return q;
  10. }
  11. static char*
  12. skipwhite(char *q)
  13. {
  14. while(*q==' ' || *q=='\t' || *q=='\r' || *q=='\n')
  15. q++;
  16. return q;
  17. }
  18. static char* months[] = {
  19. "jan", "feb", "mar", "apr",
  20. "may", "jun", "jul", "aug",
  21. "sep", "oct", "nov", "dec"
  22. };
  23. static int
  24. strcmplwr(char *a, char *b, int n)
  25. {
  26. char *eb;
  27. eb = b+n;
  28. while(*a && *b && b<eb){
  29. if(tolower(*a) != tolower(*b))
  30. return 1;
  31. a++;
  32. b++;
  33. }
  34. if(b==eb)
  35. return 0;
  36. return *a != *b;
  37. }
  38. int
  39. strtotm(char *p, Tm *tmp)
  40. {
  41. char *q, *r;
  42. int j;
  43. Tm tm;
  44. int delta;
  45. delta = 0;
  46. memset(&tm, 0, sizeof(tm));
  47. tm.mon = -1;
  48. tm.hour = -1;
  49. tm.min = -1;
  50. tm.year = -1;
  51. tm.mday = -1;
  52. for(p=skipwhite(p); *p; p=skipwhite(q)){
  53. q = skiptext(p);
  54. /* look for time in hh:mm[:ss] */
  55. if(r = memchr(p, ':', q-p)){
  56. tm.hour = strtol(p, 0, 10);
  57. tm.min = strtol(r+1, 0, 10);
  58. if(r = memchr(r+1, ':', q-(r+1)))
  59. tm.sec = strtol(r+1, 0, 10);
  60. else
  61. tm.sec = 0;
  62. continue;
  63. }
  64. /* look for month */
  65. for(j=0; j<12; j++)
  66. if(strcmplwr(p, months[j], 3)==0){
  67. tm.mon = j;
  68. break;
  69. }
  70. if(j!=12)
  71. continue;
  72. /* look for time zone [A-Z][A-Z]T */
  73. if(q-p==3 && 'A' <= p[0] && p[0] <= 'Z'
  74. && 'A' <= p[1] && p[1] <= 'Z' && p[2] == 'T'){
  75. strecpy(tm.zone, tm.zone+4, p);
  76. continue;
  77. }
  78. if(p[0]=='+'||p[0]=='-')
  79. if(q-p==5 && strspn(p+1, "0123456789") == 4){
  80. delta = (((p[1]-'0')*10+p[2]-'0')*60+(p[3]-'0')*10+p[4]-'0')*60;
  81. if(p[0] == '-')
  82. delta = -delta;
  83. continue;
  84. }
  85. if(strspn(p, "0123456789") == q-p){
  86. j = strtol(p, nil, 10);
  87. if(1 <= j && j <= 31)
  88. tm.mday = j;
  89. if(j >= 1900)
  90. tm.year = j-1900;
  91. }
  92. }
  93. if(tm.mon<0 || tm.year<0
  94. || tm.hour<0 || tm.min<0
  95. || tm.mday<0)
  96. return -1;
  97. *tmp = *localtime(tm2sec(&tm)-delta);
  98. return 0;
  99. }