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@@ -1,224 +1,225 b'' | |||||
1 | """Posix-specific implementation of process utilities. |
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1 | """Posix-specific implementation of process utilities. | |
2 |
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2 | |||
3 | This file is only meant to be imported by process.py, not by end-users. |
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3 | This file is only meant to be imported by process.py, not by end-users. | |
4 | """ |
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4 | """ | |
5 |
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5 | |||
6 | #----------------------------------------------------------------------------- |
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6 | #----------------------------------------------------------------------------- | |
7 | # Copyright (C) 2010-2011 The IPython Development Team |
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7 | # Copyright (C) 2010-2011 The IPython Development Team | |
8 | # |
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8 | # | |
9 | # Distributed under the terms of the BSD License. The full license is in |
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9 | # Distributed under the terms of the BSD License. The full license is in | |
10 | # the file COPYING, distributed as part of this software. |
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10 | # the file COPYING, distributed as part of this software. | |
11 | #----------------------------------------------------------------------------- |
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11 | #----------------------------------------------------------------------------- | |
12 |
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12 | |||
13 | #----------------------------------------------------------------------------- |
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13 | #----------------------------------------------------------------------------- | |
14 | # Imports |
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14 | # Imports | |
15 | #----------------------------------------------------------------------------- |
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15 | #----------------------------------------------------------------------------- | |
16 |
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16 | |||
17 | # Stdlib |
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17 | # Stdlib | |
18 | import errno |
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18 | import errno | |
19 | import os |
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19 | import os | |
20 | import subprocess as sp |
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20 | import subprocess as sp | |
21 | import sys |
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21 | import sys | |
22 |
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22 | |||
23 | import pexpect |
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23 | import pexpect | |
24 |
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24 | |||
25 | # Our own |
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25 | # Our own | |
26 | from ._process_common import getoutput, arg_split |
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26 | from ._process_common import getoutput, arg_split | |
27 | from IPython.utils import py3compat |
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27 | from IPython.utils import py3compat | |
28 | from IPython.utils.encoding import DEFAULT_ENCODING |
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28 | from IPython.utils.encoding import DEFAULT_ENCODING | |
29 |
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29 | |||
30 | #----------------------------------------------------------------------------- |
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30 | #----------------------------------------------------------------------------- | |
31 | # Function definitions |
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31 | # Function definitions | |
32 | #----------------------------------------------------------------------------- |
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32 | #----------------------------------------------------------------------------- | |
33 |
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33 | |||
34 | def _find_cmd(cmd): |
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34 | def _find_cmd(cmd): | |
35 | """Find the full path to a command using which.""" |
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35 | """Find the full path to a command using which.""" | |
36 |
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36 | |||
37 | path = sp.Popen(['/usr/bin/env', 'which', cmd], |
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37 | path = sp.Popen(['/usr/bin/env', 'which', cmd], | |
38 | stdout=sp.PIPE, stderr=sp.PIPE).communicate()[0] |
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38 | stdout=sp.PIPE, stderr=sp.PIPE).communicate()[0] | |
39 | return py3compat.decode(path) |
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39 | return py3compat.decode(path) | |
40 |
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40 | |||
41 |
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41 | |||
42 | class ProcessHandler(object): |
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42 | class ProcessHandler(object): | |
43 | """Execute subprocesses under the control of pexpect. |
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43 | """Execute subprocesses under the control of pexpect. | |
44 | """ |
|
44 | """ | |
45 | # Timeout in seconds to wait on each reading of the subprocess' output. |
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45 | # Timeout in seconds to wait on each reading of the subprocess' output. | |
46 | # This should not be set too low to avoid cpu overusage from our side, |
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46 | # This should not be set too low to avoid cpu overusage from our side, | |
47 | # since we read in a loop whose period is controlled by this timeout. |
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47 | # since we read in a loop whose period is controlled by this timeout. | |
48 | read_timeout = 0.05 |
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48 | read_timeout = 0.05 | |
49 |
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49 | |||
50 | # Timeout to give a process if we receive SIGINT, between sending the |
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50 | # Timeout to give a process if we receive SIGINT, between sending the | |
51 | # SIGINT to the process and forcefully terminating it. |
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51 | # SIGINT to the process and forcefully terminating it. | |
52 | terminate_timeout = 0.2 |
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52 | terminate_timeout = 0.2 | |
53 |
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53 | |||
54 | # File object where stdout and stderr of the subprocess will be written |
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54 | # File object where stdout and stderr of the subprocess will be written | |
55 | logfile = None |
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55 | logfile = None | |
56 |
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56 | |||
57 | # Shell to call for subprocesses to execute |
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57 | # Shell to call for subprocesses to execute | |
58 | _sh = None |
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58 | _sh = None | |
59 |
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59 | |||
60 | @property |
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60 | @property | |
61 | def sh(self): |
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61 | def sh(self): | |
62 |
if self._sh is None: |
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62 | if self._sh is None: | |
63 | self._sh = pexpect.which('sh') |
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63 | shell_name = os.environ.get("SHELL", "sh") | |
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64 | self._sh = pexpect.which(shell_name) | |||
64 | if self._sh is None: |
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65 | if self._sh is None: | |
65 |
raise OSError('" |
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66 | raise OSError('"{}" shell not found'.format(shell_name)) | |
66 |
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67 | |||
67 | return self._sh |
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68 | return self._sh | |
68 |
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69 | |||
69 | def __init__(self, logfile=None, read_timeout=None, terminate_timeout=None): |
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70 | def __init__(self, logfile=None, read_timeout=None, terminate_timeout=None): | |
70 | """Arguments are used for pexpect calls.""" |
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71 | """Arguments are used for pexpect calls.""" | |
71 | self.read_timeout = (ProcessHandler.read_timeout if read_timeout is |
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72 | self.read_timeout = (ProcessHandler.read_timeout if read_timeout is | |
72 | None else read_timeout) |
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73 | None else read_timeout) | |
73 | self.terminate_timeout = (ProcessHandler.terminate_timeout if |
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74 | self.terminate_timeout = (ProcessHandler.terminate_timeout if | |
74 | terminate_timeout is None else |
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75 | terminate_timeout is None else | |
75 | terminate_timeout) |
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76 | terminate_timeout) | |
76 | self.logfile = sys.stdout if logfile is None else logfile |
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77 | self.logfile = sys.stdout if logfile is None else logfile | |
77 |
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78 | |||
78 | def getoutput(self, cmd): |
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79 | def getoutput(self, cmd): | |
79 | """Run a command and return its stdout/stderr as a string. |
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80 | """Run a command and return its stdout/stderr as a string. | |
80 |
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81 | |||
81 | Parameters |
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82 | Parameters | |
82 | ---------- |
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83 | ---------- | |
83 | cmd : str |
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84 | cmd : str | |
84 | A command to be executed in the system shell. |
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85 | A command to be executed in the system shell. | |
85 |
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86 | |||
86 | Returns |
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87 | Returns | |
87 | ------- |
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88 | ------- | |
88 | output : str |
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89 | output : str | |
89 | A string containing the combination of stdout and stderr from the |
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90 | A string containing the combination of stdout and stderr from the | |
90 | subprocess, in whatever order the subprocess originally wrote to its |
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91 | subprocess, in whatever order the subprocess originally wrote to its | |
91 | file descriptors (so the order of the information in this string is the |
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92 | file descriptors (so the order of the information in this string is the | |
92 | correct order as would be seen if running the command in a terminal). |
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93 | correct order as would be seen if running the command in a terminal). | |
93 | """ |
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94 | """ | |
94 | try: |
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95 | try: | |
95 | return pexpect.run(self.sh, args=['-c', cmd]).replace('\r\n', '\n') |
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96 | return pexpect.run(self.sh, args=['-c', cmd]).replace('\r\n', '\n') | |
96 | except KeyboardInterrupt: |
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97 | except KeyboardInterrupt: | |
97 | print('^C', file=sys.stderr, end='') |
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98 | print('^C', file=sys.stderr, end='') | |
98 |
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99 | |||
99 | def getoutput_pexpect(self, cmd): |
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100 | def getoutput_pexpect(self, cmd): | |
100 | """Run a command and return its stdout/stderr as a string. |
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101 | """Run a command and return its stdout/stderr as a string. | |
101 |
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102 | |||
102 | Parameters |
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103 | Parameters | |
103 | ---------- |
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104 | ---------- | |
104 | cmd : str |
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105 | cmd : str | |
105 | A command to be executed in the system shell. |
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106 | A command to be executed in the system shell. | |
106 |
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107 | |||
107 | Returns |
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108 | Returns | |
108 | ------- |
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109 | ------- | |
109 | output : str |
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110 | output : str | |
110 | A string containing the combination of stdout and stderr from the |
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111 | A string containing the combination of stdout and stderr from the | |
111 | subprocess, in whatever order the subprocess originally wrote to its |
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112 | subprocess, in whatever order the subprocess originally wrote to its | |
112 | file descriptors (so the order of the information in this string is the |
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113 | file descriptors (so the order of the information in this string is the | |
113 | correct order as would be seen if running the command in a terminal). |
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114 | correct order as would be seen if running the command in a terminal). | |
114 | """ |
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115 | """ | |
115 | try: |
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116 | try: | |
116 | return pexpect.run(self.sh, args=['-c', cmd]).replace('\r\n', '\n') |
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117 | return pexpect.run(self.sh, args=['-c', cmd]).replace('\r\n', '\n') | |
117 | except KeyboardInterrupt: |
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118 | except KeyboardInterrupt: | |
118 | print('^C', file=sys.stderr, end='') |
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119 | print('^C', file=sys.stderr, end='') | |
119 |
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120 | |||
120 | def system(self, cmd): |
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121 | def system(self, cmd): | |
121 | """Execute a command in a subshell. |
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122 | """Execute a command in a subshell. | |
122 |
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123 | |||
123 | Parameters |
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124 | Parameters | |
124 | ---------- |
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125 | ---------- | |
125 | cmd : str |
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126 | cmd : str | |
126 | A command to be executed in the system shell. |
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127 | A command to be executed in the system shell. | |
127 |
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128 | |||
128 | Returns |
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129 | Returns | |
129 | ------- |
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130 | ------- | |
130 | int : child's exitstatus |
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131 | int : child's exitstatus | |
131 | """ |
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132 | """ | |
132 | # Get likely encoding for the output. |
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133 | # Get likely encoding for the output. | |
133 | enc = DEFAULT_ENCODING |
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134 | enc = DEFAULT_ENCODING | |
134 |
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135 | |||
135 | # Patterns to match on the output, for pexpect. We read input and |
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136 | # Patterns to match on the output, for pexpect. We read input and | |
136 | # allow either a short timeout or EOF |
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137 | # allow either a short timeout or EOF | |
137 | patterns = [pexpect.TIMEOUT, pexpect.EOF] |
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138 | patterns = [pexpect.TIMEOUT, pexpect.EOF] | |
138 | # the index of the EOF pattern in the list. |
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139 | # the index of the EOF pattern in the list. | |
139 | # even though we know it's 1, this call means we don't have to worry if |
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140 | # even though we know it's 1, this call means we don't have to worry if | |
140 | # we change the above list, and forget to change this value: |
|
141 | # we change the above list, and forget to change this value: | |
141 | EOF_index = patterns.index(pexpect.EOF) |
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142 | EOF_index = patterns.index(pexpect.EOF) | |
142 | # The size of the output stored so far in the process output buffer. |
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143 | # The size of the output stored so far in the process output buffer. | |
143 | # Since pexpect only appends to this buffer, each time we print we |
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144 | # Since pexpect only appends to this buffer, each time we print we | |
144 | # record how far we've printed, so that next time we only print *new* |
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145 | # record how far we've printed, so that next time we only print *new* | |
145 | # content from the buffer. |
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146 | # content from the buffer. | |
146 | out_size = 0 |
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147 | out_size = 0 | |
147 | try: |
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148 | try: | |
148 | # Since we're not really searching the buffer for text patterns, we |
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149 | # Since we're not really searching the buffer for text patterns, we | |
149 | # can set pexpect's search window to be tiny and it won't matter. |
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150 | # can set pexpect's search window to be tiny and it won't matter. | |
150 | # We only search for the 'patterns' timeout or EOF, which aren't in |
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151 | # We only search for the 'patterns' timeout or EOF, which aren't in | |
151 | # the text itself. |
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152 | # the text itself. | |
152 | #child = pexpect.spawn(pcmd, searchwindowsize=1) |
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153 | #child = pexpect.spawn(pcmd, searchwindowsize=1) | |
153 | if hasattr(pexpect, 'spawnb'): |
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154 | if hasattr(pexpect, 'spawnb'): | |
154 | child = pexpect.spawnb(self.sh, args=['-c', cmd]) # Pexpect-U |
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155 | child = pexpect.spawnb(self.sh, args=['-c', cmd]) # Pexpect-U | |
155 | else: |
|
156 | else: | |
156 | child = pexpect.spawn(self.sh, args=['-c', cmd]) # Vanilla Pexpect |
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157 | child = pexpect.spawn(self.sh, args=['-c', cmd]) # Vanilla Pexpect | |
157 | flush = sys.stdout.flush |
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158 | flush = sys.stdout.flush | |
158 | while True: |
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159 | while True: | |
159 | # res is the index of the pattern that caused the match, so we |
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160 | # res is the index of the pattern that caused the match, so we | |
160 | # know whether we've finished (if we matched EOF) or not |
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161 | # know whether we've finished (if we matched EOF) or not | |
161 | res_idx = child.expect_list(patterns, self.read_timeout) |
|
162 | res_idx = child.expect_list(patterns, self.read_timeout) | |
162 | print(child.before[out_size:].decode(enc, 'replace'), end='') |
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163 | print(child.before[out_size:].decode(enc, 'replace'), end='') | |
163 | flush() |
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164 | flush() | |
164 | if res_idx==EOF_index: |
|
165 | if res_idx==EOF_index: | |
165 | break |
|
166 | break | |
166 | # Update the pointer to what we've already printed |
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167 | # Update the pointer to what we've already printed | |
167 | out_size = len(child.before) |
|
168 | out_size = len(child.before) | |
168 | except KeyboardInterrupt: |
|
169 | except KeyboardInterrupt: | |
169 | # We need to send ^C to the process. The ascii code for '^C' is 3 |
|
170 | # We need to send ^C to the process. The ascii code for '^C' is 3 | |
170 | # (the character is known as ETX for 'End of Text', see |
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171 | # (the character is known as ETX for 'End of Text', see | |
171 | # curses.ascii.ETX). |
|
172 | # curses.ascii.ETX). | |
172 | child.sendline(chr(3)) |
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173 | child.sendline(chr(3)) | |
173 | # Read and print any more output the program might produce on its |
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174 | # Read and print any more output the program might produce on its | |
174 | # way out. |
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175 | # way out. | |
175 | try: |
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176 | try: | |
176 | out_size = len(child.before) |
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177 | out_size = len(child.before) | |
177 | child.expect_list(patterns, self.terminate_timeout) |
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178 | child.expect_list(patterns, self.terminate_timeout) | |
178 | print(child.before[out_size:].decode(enc, 'replace'), end='') |
|
179 | print(child.before[out_size:].decode(enc, 'replace'), end='') | |
179 | sys.stdout.flush() |
|
180 | sys.stdout.flush() | |
180 | except KeyboardInterrupt: |
|
181 | except KeyboardInterrupt: | |
181 | # Impatient users tend to type it multiple times |
|
182 | # Impatient users tend to type it multiple times | |
182 | pass |
|
183 | pass | |
183 | finally: |
|
184 | finally: | |
184 | # Ensure the subprocess really is terminated |
|
185 | # Ensure the subprocess really is terminated | |
185 | child.terminate(force=True) |
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186 | child.terminate(force=True) | |
186 | # add isalive check, to ensure exitstatus is set: |
|
187 | # add isalive check, to ensure exitstatus is set: | |
187 | child.isalive() |
|
188 | child.isalive() | |
188 |
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189 | |||
189 | # We follow the subprocess pattern, returning either the exit status |
|
190 | # We follow the subprocess pattern, returning either the exit status | |
190 | # as a positive number, or the terminating signal as a negative |
|
191 | # as a positive number, or the terminating signal as a negative | |
191 | # number. |
|
192 | # number. | |
192 | # on Linux, sh returns 128+n for signals terminating child processes on Linux |
|
193 | # on Linux, sh returns 128+n for signals terminating child processes on Linux | |
193 | # on BSD (OS X), the signal code is set instead |
|
194 | # on BSD (OS X), the signal code is set instead | |
194 | if child.exitstatus is None: |
|
195 | if child.exitstatus is None: | |
195 | # on WIFSIGNALED, pexpect sets signalstatus, leaving exitstatus=None |
|
196 | # on WIFSIGNALED, pexpect sets signalstatus, leaving exitstatus=None | |
196 | if child.signalstatus is None: |
|
197 | if child.signalstatus is None: | |
197 | # this condition may never occur, |
|
198 | # this condition may never occur, | |
198 | # but let's be certain we always return an integer. |
|
199 | # but let's be certain we always return an integer. | |
199 | return 0 |
|
200 | return 0 | |
200 | return -child.signalstatus |
|
201 | return -child.signalstatus | |
201 | if child.exitstatus > 128: |
|
202 | if child.exitstatus > 128: | |
202 | return -(child.exitstatus - 128) |
|
203 | return -(child.exitstatus - 128) | |
203 | return child.exitstatus |
|
204 | return child.exitstatus | |
204 |
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205 | |||
205 |
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206 | |||
206 | # Make system() with a functional interface for outside use. Note that we use |
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207 | # Make system() with a functional interface for outside use. Note that we use | |
207 | # getoutput() from the _common utils, which is built on top of popen(). Using |
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208 | # getoutput() from the _common utils, which is built on top of popen(). Using | |
208 | # pexpect to get subprocess output produces difficult to parse output, since |
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209 | # pexpect to get subprocess output produces difficult to parse output, since | |
209 | # programs think they are talking to a tty and produce highly formatted output |
|
210 | # programs think they are talking to a tty and produce highly formatted output | |
210 | # (ls is a good example) that makes them hard. |
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211 | # (ls is a good example) that makes them hard. | |
211 | system = ProcessHandler().system |
|
212 | system = ProcessHandler().system | |
212 |
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213 | |||
213 | def check_pid(pid): |
|
214 | def check_pid(pid): | |
214 | try: |
|
215 | try: | |
215 | os.kill(pid, 0) |
|
216 | os.kill(pid, 0) | |
216 | except OSError as err: |
|
217 | except OSError as err: | |
217 | if err.errno == errno.ESRCH: |
|
218 | if err.errno == errno.ESRCH: | |
218 | return False |
|
219 | return False | |
219 | elif err.errno == errno.EPERM: |
|
220 | elif err.errno == errno.EPERM: | |
220 | # Don't have permission to signal the process - probably means it exists |
|
221 | # Don't have permission to signal the process - probably means it exists | |
221 | return True |
|
222 | return True | |
222 | raise |
|
223 | raise | |
223 | else: |
|
224 | else: | |
224 | return True |
|
225 | return True |
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