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Merged
jserv merged 1 commit into from
Apr 8, 2025
Merged

Add snprintf implementation and refine printf family funcs #185

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134 changes: 49 additions & 85 deletions lib/c.c
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Original file line number Diff line number Diff line change
Expand Up @@ -13,6 +13,9 @@
#define true 1
#define false 0

#define INT_MAX 0x7fffffff
#define INT_MIN 0x80000000

#if defined(__arm__)
#define __SIZEOF_POINTER__ 4
#define __syscall_exit 1
Expand Down Expand Up @@ -288,60 +291,65 @@ int __format(char *buffer,
return bi;
}

void printf(char *str, ...)
int __format_to_buf(char *buffer, char *format, int *var_args, int size)
{
int *var_args = &str + 4;
char buffer[200];
int si = 0, bi = 0, pi = 0;

while (str[si]) {
if (str[si] != '%') {
buffer[bi] = str[si];
if (size == 0)
return 0;

while (format[si] && bi < size - 1) {
if (format[si] != '%') {
buffer[bi] = format[si];
bi++;
si++;
} else {
int w = 0, zp = 0, pp = 0;
int w = 0, zp = 0, pp = 0, v = var_args[pi], l;

si++;
if (str[si] == '#') {
if (format[si] == '#') {
pp = 1;
si++;
}
if (str[si] == '0') {
if (format[si] == '0') {
zp = 1;
si++;
}
if (str[si] >= '1' && str[si] <= '9') {
w = str[si] - '0';
if (format[si] >= '1' && format[si] <= '9') {
w = format[si] - '0';
si++;
while (str[si] >= '0' && str[si] <= '9') {
while (format[si] >= '0' && format[si] <= '9') {
w *= 10;
w += str[si] - '0';
w += format[si] - '0';
si++;
}
}
if (str[si] == 's') {
switch (format[si]) {
case 's':
/* append param pi as string */
int l = strlen(var_args[pi]);
strcpy(buffer + bi, var_args[pi]);
l = strlen(v);
l = l < size - bi ? l : size - bi;
strncpy(buffer + bi, v, l);
bi += l;
} else if (str[si] == 'c') {
break;
case 'c':
/* append param pi as char */
buffer[bi] = var_args[pi];
buffer[bi] = v;
bi += 1;
} else if (str[si] == 'o') {
break;
case 'o':
/* append param as octal */
int v = var_args[pi];
bi += __format(buffer + bi, v, w, zp, 8, pp);
} else if (str[si] == 'd') {
break;
case 'd':
/* append param as decimal */
int v = var_args[pi];
bi += __format(buffer + bi, v, w, zp, 10, 0);
} else if (str[si] == 'x') {
break;
case 'x':
/* append param as hex */
int v = var_args[pi];
bi += __format(buffer + bi, v, w, zp, 16, pp);
} else if (str[si] == '%') {
break;
case '%':
/* append literal '%' character */
buffer[bi] = '%';
bi++;
Expand All @@ -352,71 +360,27 @@ void printf(char *str, ...)
si++;
}
}
buffer[bi] = 0;
__syscall(__syscall_write, 1, buffer, bi);

int len = size - 1 > bi ? bi : size - 1;
buffer[len] = 0;
return len;
}

void sprintf(char *buffer, char *str, ...)
int printf(char *str, ...)
{
int *var_args = &str + 4;
int si = 0, bi = 0, pi = 0;
char buffer[200];
int len = __format_to_buf(buffer, str, &str + 4, INT_MAX);
return __syscall(__syscall_write, 1, buffer, len);
}

while (str[si]) {
if (str[si] != '%') {
buffer[bi] = str[si];
bi++;
si++;
} else {
int w = 0, zp = 0, pp = 0;
int sprintf(char *buffer, char *str, ...)
{
return __format_to_buf(buffer, str, &str + 4, INT_MAX);
}

si++;
if (str[si] == '#') {
pp = 1;
si++;
}
if (str[si] == '0') {
zp = 1;
si++;
}
if (str[si] >= '1' && str[si] <= '9') {
w = str[si] - '0';
si++;
if (str[si] >= '0' && str[si] <= '9') {
w *= 10;
w += str[si] - '0';
si++;
}
}
switch (str[si]) {
case 37: /* % */
buffer[bi++] = '%';
si++;
continue;
case 99: /* c */
buffer[bi++] = var_args[pi];
break;
case 115: /* s */
strcpy(buffer + bi, var_args[pi]);
bi += strlen(var_args[pi]);
break;
case 111: /* o */
bi += __format(buffer + bi, var_args[pi], w, zp, 8, pp);
break;
case 100: /* d */
bi += __format(buffer + bi, var_args[pi], w, zp, 10, 0);
break;
case 120: /* x */
bi += __format(buffer + bi, var_args[pi], w, zp, 16, pp);
break;
default:
abort();
break;
}
pi++;
si++;
}
}
buffer[bi] = 0;
int snprintf(char *buffer, int n, char *str, ...)
{
return __format_to_buf(buffer, str, &str + 4, n);
}

int __free_all();
Expand Down
8 changes: 4 additions & 4 deletions src/defs.h
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Original file line number Diff line number Diff line change
Expand Up @@ -17,17 +17,17 @@
#define MAX_VAR_LEN 32
#define MAX_TYPE_LEN 32
#define MAX_PARAMS 8
#define MAX_LOCALS 1500
#define MAX_LOCALS 1600
#define MAX_FIELDS 64
#define MAX_FUNCS 512
#define MAX_TYPES 64
#define MAX_IR_INSTR 50000
#define MAX_IR_INSTR 60000
#define MAX_BB_PRED 128
#define MAX_BB_DOM_SUCC 64
#define MAX_BB_RDOM_SUCC 256
#define MAX_GLOBAL_IR 256
#define MAX_LABEL 4096
#define MAX_SOURCE 327680
#define MAX_SOURCE 524288
#define MAX_CODE 262144
#define MAX_DATA 262144
#define MAX_SYMTAB 65536
Expand All @@ -39,7 +39,7 @@
#define MAX_CASES 128
#define MAX_NESTING 128
#define MAX_OPERAND_STACK_SIZE 32
#define MAX_ANALYSIS_STACK_SIZE 750
#define MAX_ANALYSIS_STACK_SIZE 800

/* Default capacities for common data structures */
/* Default arena size is initialized with 256 KiB */
Expand Down
13 changes: 7 additions & 6 deletions src/parser.c
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Original file line number Diff line number Diff line change
Expand Up @@ -2621,6 +2621,9 @@ basic_block_t *read_body_statement(block_t *parent, basic_block_t *bb)
if (lex_peek(T_numeric, NULL)) {
case_val = read_numeric_constant(token_str);
lex_expect(T_numeric); /* already read it */
} else if (lex_peek(T_char, token)) {
case_val = token[0];
lex_expect(T_char);
} else {
constant_t *cd = find_constant(token_str);
case_val = cd->value;
Expand Down Expand Up @@ -3401,17 +3404,15 @@ void load_source_file(char *file)
}
if (!strncmp(buffer, "#include ", 9) && (buffer[9] == '"')) {
char path[MAX_LINE_LEN];
int c = strlen(file) - 1;
int c = strlen(file) - 1, inclusion_path_len = strlen(buffer) - 11;
while (c > 0 && file[c] != '/')
c--;
if (c) {
/* prepend directory name */
strncpy(path, file, c + 1);
c++;
snprintf(path, c + 2, "%s", file);
}
path[c] = 0;
buffer[strlen(buffer) - 2] = 0;
strcpy(path + c, buffer + 10);

snprintf(path + c + 1, inclusion_path_len, "%s", buffer + 10);
load_source_file(path);
} else {
strcpy(SOURCE + source_idx, buffer);
Expand Down
63 changes: 63 additions & 0 deletions tests/driver.sh
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Original file line number Diff line number Diff line change
Expand Up @@ -1611,4 +1611,67 @@ int main()
}
EOF

# printf family, including truncation and zero size input
try_output 11 "Hello World" << EOF
int main() {
int written = printf("Hello World");
return written;
}
EOF

# tests printf returns EBADF (errno 9) when stdout is closed
try_output 1 "" << EOF
int main()
{
__syscall(__syscall_close, 1);
int written = printf("Hello\n");
return written == -9;
}
EOF

try_output 11 "Hello World" << EOF
int main() {
char buffer[50];
int written = sprintf(buffer, "Hello World");
printf("%s", buffer);
return written;
}
EOF

try_output 16 "Hello World 1123" << EOF
int main() {
char buffer[50];
int written = sprintf(buffer, "Hello %s %d", "World", 1123);
printf("%s", buffer);
return written;
}
EOF

try_output 16 "Hello World 1123" << EOF
int main() {
char buffer[50];
int written = snprintf(buffer, 50, "Hello %s %d", "World", 1123);
printf("%s", buffer);
return written;
}
EOF

try_output 0 "" << EOF
int main() {
char buffer[20];
int written = snprintf(buffer, 0, "Number: %d", -37);
printf("%s", buffer);
return written;
}
EOF

try_output 9 "Number: -" << EOF
int main() {
char buffer[10];
int written = snprintf(buffer, 10, "Number: %d", -37);
printf("%s", buffer);
return written;
}
EOF

echo OK
2 changes: 1 addition & 1 deletion tests/snapshots/fib-arm.json
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2 changes: 1 addition & 1 deletion tests/snapshots/fib-riscv.json
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2 changes: 1 addition & 1 deletion tests/snapshots/hello-arm.json
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2 changes: 1 addition & 1 deletion tests/snapshots/hello-riscv.json
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