This source file includes following definitions.
- db_term
- db_unary
- db_mult_expr
- db_add_expr
- db_shift_expr
- db_expression
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33 #include <sys/param.h>
34 #include <sys/proc.h>
35
36 #include <uvm/uvm_extern.h>
37
38 #include <machine/db_machdep.h>
39
40 #include <ddb/db_lex.h>
41 #include <ddb/db_access.h>
42 #include <ddb/db_command.h>
43 #include <ddb/db_sym.h>
44 #include <ddb/db_extern.h>
45 #include <ddb/db_variables.h>
46
47 boolean_t
48 db_term(db_expr_t *valuep)
49 {
50 int t;
51
52 t = db_read_token();
53 if (t == tIDENT) {
54 if (!db_value_of_name(db_tok_string, valuep)) {
55 db_error("Symbol not found\n");
56
57 }
58 return (TRUE);
59 }
60 if (t == tNUMBER) {
61 *valuep = db_tok_number;
62 return (TRUE);
63 }
64 if (t == tDOT) {
65 *valuep = (db_expr_t)db_dot;
66 return (TRUE);
67 }
68 if (t == tDOTDOT) {
69 *valuep = (db_expr_t)db_prev;
70 return (TRUE);
71 }
72 if (t == tPLUS) {
73 *valuep = (db_expr_t) db_next;
74 return (TRUE);
75 }
76 if (t == tDITTO) {
77 *valuep = (db_expr_t)db_last_addr;
78 return (TRUE);
79 }
80 if (t == tDOLLAR) {
81 if (!db_get_variable(valuep))
82 return (FALSE);
83 return (TRUE);
84 }
85 if (t == tLPAREN) {
86 if (!db_expression(valuep)) {
87 db_error("Syntax error\n");
88
89 }
90 t = db_read_token();
91 if (t != tRPAREN) {
92 db_error("Syntax error\n");
93
94 }
95 return (TRUE);
96 }
97 db_unread_token(t);
98 return (FALSE);
99 }
100
101 boolean_t
102 db_unary(db_expr_t *valuep)
103 {
104 int t;
105
106 t = db_read_token();
107 if (t == tMINUS) {
108 if (!db_unary(valuep)) {
109 db_error("Syntax error\n");
110
111 }
112 *valuep = -*valuep;
113 return (TRUE);
114 }
115 if (t == tSTAR) {
116
117 if (!db_unary(valuep)) {
118 db_error("Syntax error\n");
119
120 }
121 *valuep = db_get_value((db_addr_t)*valuep, sizeof(int), FALSE);
122 return (TRUE);
123 }
124 db_unread_token(t);
125 return (db_term(valuep));
126 }
127
128 boolean_t
129 db_mult_expr(db_expr_t *valuep)
130 {
131 db_expr_t lhs, rhs;
132 int t;
133
134 if (!db_unary(&lhs))
135 return (FALSE);
136
137 t = db_read_token();
138 while (t == tSTAR || t == tSLASH || t == tPCT || t == tHASH) {
139 if (!db_term(&rhs)) {
140 db_error("Syntax error\n");
141
142 }
143 if (t == tSTAR)
144 lhs *= rhs;
145 else {
146 if (rhs == 0) {
147 db_error("Divide by 0\n");
148
149 }
150 if (t == tSLASH)
151 lhs /= rhs;
152 else if (t == tPCT)
153 lhs %= rhs;
154 else
155 lhs = ((lhs+rhs-1)/rhs)*rhs;
156 }
157 t = db_read_token();
158 }
159 db_unread_token(t);
160 *valuep = lhs;
161 return (TRUE);
162 }
163
164 boolean_t
165 db_add_expr(db_expr_t *valuep)
166 {
167 db_expr_t lhs, rhs;
168 int t;
169
170 if (!db_mult_expr(&lhs))
171 return (FALSE);
172
173 t = db_read_token();
174 while (t == tPLUS || t == tMINUS) {
175 if (!db_mult_expr(&rhs)) {
176 db_error("Syntax error\n");
177
178 }
179 if (t == tPLUS)
180 lhs += rhs;
181 else
182 lhs -= rhs;
183 t = db_read_token();
184 }
185 db_unread_token(t);
186 *valuep = lhs;
187 return (TRUE);
188 }
189
190 boolean_t
191 db_shift_expr(db_expr_t *valuep)
192 {
193 db_expr_t lhs, rhs;
194 int t;
195
196 if (!db_add_expr(&lhs))
197 return (FALSE);
198
199 t = db_read_token();
200 while (t == tSHIFT_L || t == tSHIFT_R) {
201 if (!db_add_expr(&rhs)) {
202 db_error("Syntax error\n");
203
204 }
205 if (rhs < 0) {
206 db_error("Negative shift amount\n");
207
208 }
209 if (t == tSHIFT_L)
210 lhs <<= rhs;
211 else {
212
213 lhs = (unsigned) lhs >> rhs;
214 }
215 t = db_read_token();
216 }
217 db_unread_token(t);
218 *valuep = lhs;
219 return (TRUE);
220 }
221
222 int
223 db_expression(db_expr_t *valuep)
224 {
225 return (db_shift_expr(valuep));
226 }