1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
include <tbset.h>
# TABVAR -- Retrieve a table column given its name
#
# B.Simon 03-May-91 Original
# B.Simon 23-Jun-97 Peicewise evaluation of column
procedure tabvar (stack, colname)
pointer stack # u: Expression stack pointer
char colname[ARB] # i: Column name
#--
include "../tabvar.com"
int i, coltype, nrows
pointer sp, nullbuf, buffer, errmsg, cp
string badcolnam "Column name not found (%s)"
bool streq()
int tbcigi()
pointer stk_alloc()
begin
# Allocate dynamic memory for strings
call smark (sp)
call salloc (errmsg, SZ_LINE, TY_CHAR)
# Get column pointer from name
call tbcfnd (tabptr, colname, cp, 1)
if (cp == NULL) {
if (streq (colname, "rownum")) {
call rowvar (stack)
return
} else {
call sprintf (Memc[errmsg], SZ_LINE, badcolnam)
call pargstr (colname)
call error (1, Memc[errmsg])
}
}
# Get column type
coltype = tbcigi (cp, TBL_COL_DATATYPE)
if (coltype == TY_BOOL || coltype == TY_SHORT || coltype == TY_LONG) {
coltype = TY_INT
} else if (coltype < 0) {
coltype = TY_DOUBLE
}
# Allocate a buffer on the expression evaluator stack
nrows = (lastrow - firstrow) + 1
call malloc (nullbuf, nrows, TY_BOOL)
buffer = stk_alloc (stack, nrows, coltype)
# Copy the table column into the buffer
# Substitute the user supplied vales for nulls
switch (coltype) {
case TY_SHORT, TY_INT, TY_LONG:
call tbcgti (tabptr, cp, Memi[buffer], Memb[nullbuf],
firstrow, lastrow)
do i = 0, nrows-1 {
if (Memb[nullbuf+i])
Memi[buffer+i] = nullval
}
case TY_REAL:
call tbcgtr (tabptr, cp, Memr[buffer], Memb[nullbuf],
firstrow, lastrow)
do i = 0, nrows-1 {
if (Memb[nullbuf+i])
Memr[buffer+i] = nullval
}
case TY_DOUBLE:
call tbcgtd (tabptr, cp, Memd[buffer], Memb[nullbuf],
firstrow, lastrow)
do i = 0, nrows-1 {
if (Memb[nullbuf+i])
Memd[buffer+i] = nullval
}
}
# Update the null array
call stk_ornull (stack, Memb[nullbuf], nrows)
call mfree (nullbuf, TY_BOOL)
call sfree (sp)
end
# ROWVAR -- Handle the variable "rownum"
procedure rowvar (stack)
pointer stack # u: Expression stack pointer
#--
include "../tabvar.com"
int irow, nrows
pointer buffer
pointer stk_alloc()
begin
# Allocate a buffer on the expression evaluator stack
nrows = (lastrow - firstrow) + 1
buffer = stk_alloc (stack, nrows, TY_INT)
# Fill the buffer with the row number
do irow = 0, nrows-1
Memi[buffer+irow] = firstrow + irow
end
|
