1 //===-- Format specifier converter implmentation for scanf -----*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "src/stdio/scanf_core/converter.h"
10
11 #include "src/__support/ctype_utils.h"
12 #include "src/stdio/scanf_core/core_structs.h"
13 #include "src/stdio/scanf_core/reader.h"
14
15 #ifndef LIBC_COPT_SCANF_DISABLE_FLOAT
16 #include "src/stdio/scanf_core/float_converter.h"
17 #endif // LIBC_COPT_SCANF_DISABLE_FLOAT
18 #include "src/stdio/scanf_core/current_pos_converter.h"
19 #include "src/stdio/scanf_core/int_converter.h"
20 #include "src/stdio/scanf_core/ptr_converter.h"
21 #include "src/stdio/scanf_core/string_converter.h"
22
23 #include <stddef.h>
24
25 namespace LIBC_NAMESPACE {
26 namespace scanf_core {
27
convert(Reader * reader,const FormatSection & to_conv)28 int convert(Reader *reader, const FormatSection &to_conv) {
29 int ret_val = 0;
30 switch (to_conv.conv_name) {
31 case '%':
32 return raw_match(reader, "%");
33 case 's':
34 ret_val = raw_match(reader, " ");
35 if (ret_val != READ_OK)
36 return ret_val;
37 return convert_string(reader, to_conv);
38 case 'c':
39 case '[':
40 return convert_string(reader, to_conv);
41 case 'd':
42 case 'i':
43 case 'u':
44 case 'o':
45 case 'x':
46 case 'X':
47 ret_val = raw_match(reader, " ");
48 if (ret_val != READ_OK)
49 return ret_val;
50 return convert_int(reader, to_conv);
51 #ifndef LIBC_COPT_SCANF_DISABLE_FLOAT
52 case 'f':
53 case 'F':
54 case 'e':
55 case 'E':
56 case 'a':
57 case 'A':
58 case 'g':
59 case 'G':
60 ret_val = raw_match(reader, " ");
61 if (ret_val != READ_OK)
62 return ret_val;
63 return convert_float(reader, to_conv);
64 #endif // LIBC_COPT_SCANF_DISABLE_FLOAT
65 case 'n':
66 return convert_current_pos(reader, to_conv);
67 case 'p':
68 ret_val = raw_match(reader, " ");
69 if (ret_val != READ_OK)
70 return ret_val;
71 return convert_pointer(reader, to_conv);
72 default:
73 return raw_match(reader, to_conv.raw_string);
74 }
75 return -1;
76 }
77
78 // raw_string is assumed to have a positive size.
raw_match(Reader * reader,cpp::string_view raw_string)79 int raw_match(Reader *reader, cpp::string_view raw_string) {
80 char cur_char = reader->getc();
81 int ret_val = READ_OK;
82 for (size_t i = 0; i < raw_string.size(); ++i) {
83 // Any space character matches any number of space characters.
84 if (internal::isspace(raw_string[i])) {
85 while (internal::isspace(cur_char)) {
86 cur_char = reader->getc();
87 }
88 } else {
89 if (raw_string[i] == cur_char) {
90 cur_char = reader->getc();
91 } else {
92 ret_val = MATCHING_FAILURE;
93 break;
94 }
95 }
96 }
97 reader->ungetc(cur_char);
98 return ret_val;
99 }
100
101 } // namespace scanf_core
102 } // namespace LIBC_NAMESPACE
103