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manipulatorsInput.cfa @ 0860d9c

Last change on this file since 0860d9c was 0860d9c, checked in by Michael Brooks <mlbrooks@…>, 9 months ago

Fix read-to-variable-length-string cases when internal buffer fills.

Also fix read-to-cstring ability to give no-exception cases when an entire buffer fills.

The added test cases run, and fail, when run against prior libcfa.
Doing so illustrates a CFA-string-level bug.
Doing so illustrates a C-string-level changed semantics.

At the CFA-string level, the bug was, when reading strings of just the right length,
what should be two reads ("abc" then "def") gets mashed into one ("abcdef").
These cases are clearly bugs because a test program that just echoes chuncks of delimeted input would do so inaccurately.
They're just hard to drive because the relevant chunk lengths are implementation-dependent, and sometimes big.

At the C-string level, the semantic change concerns when to throw the cstring_length exception.
By this change, make the original semantics,
"An exception means the maximum number of characters was read," into
"An exception means that if the buffer were larger, then more characters would have been read."

The added test cases cover the respective stop conditions for manipulator state "%s", include, exclude, getline, and getline/delimiter.

Property mode set to 100644

File size: 6.8 KB

Line
1	//
2	// Cforall Version 1.0.0 Copyright (C) 2019 University of Waterloo
3	//
4	// manipulatorsInput.cfa --
5	//
6	// Author : Peter A. Buhr
7	// Created On : Sat Jun 8 17:58:54 2019
8	// Last Modified By : Peter A. Buhr
9	// Last Modified On : Sat Sep 2 14:27:46 2023
10	// Update Count : 65
11	//
12
13	#include <fstream.hfa>
14	#include <stdio.h> // scanf
15
16	int main() {
17	{
18	// Upfront checks to ensure buffer safety. Once these pass, the simpler `wdi(sizeof(s),s)`
19	// usage, as in the scanf alignment cases below, is justified.
20	struct {
21	char buf[8];
22	char canary;
23	} data;
24	static_assert( sizeof(data.buf) == 8 );
25	static_assert( &data.buf[8] == &data.canary ); // canary comes right after buf
26
27	void rep(const char* casename) {
28	data.canary = 42;
29	bool caught = false;
30	try {
31	sin \| wdi( sizeof(data.buf), data.buf );
32	} catch (cstring_length*) {
33	caught = true;
34	}
35	printf( "%s \"%s\"", casename, data.buf );
36	if ( caught ) {
37	printf(", exception occurred");
38	}
39	if ( data.canary == 42 ) {
40	printf(", canary ok");
41	} else {
42	printf(", canary overwritten to %d", data.canary);
43	}
44	printf("\n");
45	}
46
47	rep("pre1"); // 123456 \| 123456
48	rep("pre2"); // 1234567 \| 1234567
49	rep("pre3a"); // 12345678 \| 1234567
50	rep("pre3b"); // \| 8
51	rep("pre4a"); // 123456789 \| 1234567
52	rep("pre4b"); // \| 89
53
54	scanf("\n"); // next test does not start with %s so does not tolerate leading whitespace
55	}
56	{
57	char s[] = "yyyyyyyyyyyyyyyyyyyy";
58	const char sk_fmt[] = "%*[abc]";
59	scanf( "abc " ); scanf( sk_fmt ); for ( 5 ) scanf( "%*c" ); printf( "1 %s\n", s );
60	scanf( "%s", s ); printf( "2 %s\n", s );
61	scanf( "%*s" ); printf( "3 %s\n", s );
62	scanf( "%8s", s ); printf( "4 %s\n", s );
63	scanf( "%*8s" ); printf( "5 %s\n", s );
64
65	scanf( "%[abc]", s ); printf( "6 %s\n", s );
66	scanf( "%[^abc]", s ); printf( "7 %s\n", s );
67	scanf( "%*[abc]" ); printf( "8 %s\n", s );
68	scanf( "%*[^abc]" ); printf( "9 %s\n", s );
69	scanf( "%8[abc]", s ); printf( "10 %s\n", s );
70	scanf( "%8[^abc]", s ); printf( "11 %s\n", s );
71	scanf( "%*8[abc]" ); printf( "12 %s\n", s );
72	scanf( "%*8[^abc]" ); printf( "13 %s\n", s );
73
74	int rc;
75	s[0] = 'q'; s[1] = '\0'; rc = 99;
76	rc = scanf( "%[abc]", s ); printf( "14 rc=%d, %s\n", rc, s );
77	s[0] = 'q'; s[1] = '\0'; rc = 99;
78	rc = scanf( "%[^u]", s ); printf( "15 rc=%d, %s\n", rc, s );
79	scanf( "%*[u]" );
80	scanf("\n");
81	}
82	{
83	char s[] = "yyyyyyyyyyyyyyyyyyyy";
84	char sk[] = "abc";
85	sin \| "abc " \| skip( sk ) \| skip( 5 ); sout \| "1" \| s;
86	sin \| wdi( sizeof(s), s ); sout \| "2" \| s;
87	sin \| ignore( s ); sout \| "3" \| s;
88	sin \| wdi( sizeof(s), 8, s ); sout \| "4" \| s;
89	sin \| ignore( wdi( sizeof(s), 8, s ) ); sout \| "5" \| s;
90
91	sin \| incl( "abc", wdi( sizeof(s), s ) ); sout \| "6" \| s;
92	sin \| excl( "abc", wdi( sizeof(s), s ) ); sout \| "7" \| s;
93	sin \| ignore( incl( "abc", wdi( sizeof(s), s ) ) ); sout \| "8" \| s;
94	sin \| ignore( excl( "abc", wdi( sizeof(s), s ) ) ); sout \| "9" \| s;
95	sin \| incl( "abc", wdi( sizeof(s), 8, s ) ); sout \| "10" \| s;
96	sin \| excl( "abc", wdi( sizeof(s), 8, s ) ); sout \| "11" \| s;
97	sin \| ignore( incl( "abc", wdi( sizeof(s), 8, s ) ) ); sout \| "12" \| s;
98	sin \| ignore( excl( "abc", wdi( sizeof(s), 8, s ) ) ); sout \| "13" \| s;
99
100	s[0] = 'q'; s[1] = '\0';
101	sin \| incl( "abc", wdi( sizeof(s), s ) ); sout \| "14" \| s;
102	s[0] = 'q'; s[1] = '\0';
103	sin \| excl( "u", wdi( sizeof(s), s ) ); sout \| "15" \| s;
104	sin \| skip( "u" );
105	sin \| "\n";
106	}
107	/* Keep harmonized with collections/string-istream-manip */
108	{
109	char c;
110	sin \| c; sout \| c;
111	sin \| ignore( c ); sout \| c;
112
113	signed char sc;
114	sin \| sc; sout \| sc;
115	sin \| wdi( 3, sc ); sout \| sc;
116	sin \| ignore( sc ); sout \| sc;
117	sin \| ignore( wdi( 3, sc ) ); sout \| sc;
118
119	unsigned char usc;
120	sin \| usc; sout \| usc;
121	sin \| wdi( 3, usc ); sout \| usc;
122	sin \| ignore( usc ); sout \| usc;
123	sin \| ignore( wdi( 3, usc ) ); sout \| usc;
124
125	signed short int ssi;
126	sin \| ssi; sout \| ssi;
127	sin \| wdi( 3, ssi ); sout \| ssi;
128	sin \| ignore( ssi ); sout \| ssi;
129	sin \| ignore( wdi( 3, ssi ) ); sout \| ssi;
130
131	unsigned short int usi;
132	sin \| usi; sout \| usi;
133	sin \| wdi( 3, usi ); sout \| usi;
134	sin \| ignore( usi ); sout \| usi;
135	sin \| ignore( wdi( 3, usi ) ); sout \| usi;
136
137	signed int si;
138	sin \| si; sout \| si;
139	sin \| wdi( 3, si ); sout \| si;
140	sin \| ignore( si ); sout \| si;
141	sin \| ignore( wdi( 3, si ) ); sout \| si;
142
143	unsigned int ui;
144	sin \| ui; sout \| ui;
145	sin \| wdi( 3, ui ); sout \| ui;
146	sin \| ignore( ui ); sout \| ui;
147	sin \| ignore( wdi( 3, ui ) ); sout \| ui;
148
149	signed long int sli;
150	sin \| sli; sout \| sli;
151	sin \| wdi( 3, sli ); sout \| sli;
152	sin \| ignore( sli ); sout \| sli;
153	sin \| ignore( wdi( 3, sli ) ); sout \| sli;
154
155	unsigned long int uli;
156	sin \| uli; sout \| uli;
157	sin \| wdi( 3, uli ); sout \| uli;
158	sin \| ignore( uli ); sout \| uli;
159	sin \| ignore( wdi( 3, uli ) ); sout \| uli;
160
161	signed long long int slli;
162	sin \| slli; sout \| slli;
163	sin \| wdi( 3, slli ); sout \| slli;
164	sin \| ignore( slli ); sout \| slli;
165	sin \| ignore( wdi( 3, slli ) ); sout \| slli;
166
167	unsigned long long int ulli;
168	sin \| ulli; sout \| ulli;
169	sin \| wdi( 3, ulli ); sout \| ulli;
170	sin \| ignore( ulli ); sout \| ulli;
171	sin \| ignore( wdi( 3, ulli ) ); sout \| ulli;
172
173	float f;
174	sin \| f; sout \| f;
175	sin \| wdi( 8, f ); sout \| f;
176	sin \| ignore( f ); sout \| f;
177	sin \| ignore( wdi( 8, f ) ); sout \| f;
178
179	double d;
180	sin \| d; sout \| d;
181	sin \| wdi( 8, d ); sout \| d;
182	sin \| ignore( d ); sout \| d;
183	sin \| ignore( wdi( 8, d ) ); sout \| d;
184
185	long double ld;
186	sin \| ld; sout \| ld;
187	sin \| wdi( 8, ld ); sout \| ld;
188	sin \| ignore( ld ); sout \| ld;
189	sin \| ignore( wdi( 8, ld ) ); sout \| ld;
190
191	float _Complex fc;
192	sin \| fc; sout \| fc;
193	sin \| wdi( 8, fc ); sout \| fc;
194	sin \| ignore( fc ); sout \| fc;
195	sin \| ignore( wdi( 8, fc ) ); sout \| fc;
196
197	double _Complex dc;
198	sin \| dc; sout \| dc;
199	sin \| wdi( 8, dc ); sout \| dc;
200	sin \| ignore( dc ); sout \| dc;
201	sin \| ignore( wdi( 8, dc ) ); sout \| dc;
202
203	long double _Complex ldc;
204	sin \| ldc; sout \| ldc;
205	sin \| wdi( 8, ldc ); sout \| ldc;
206	sin \| ignore( ldc ); sout \| ldc;
207	sin \| ignore( wdi( 8, ldc ) ); sout \| ldc;
208	}
209	#if defined( __SIZEOF_INT128__ )
210	{
211	int128 val;
212	for ( 15 ) {
213	sin \| val;
214	sout \| val;
215	}
216	}
217	#endif // __SIZEOF_INT128__
218	} // main
219
220	// Local Variables: //
221	// tab-width: 4 //
222	// compile-command: "cfa -Wall -Wextra manipulatorsInput.cfa" //
223	// End: //

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